Question 1

350 Motor Mounts for 1969

admn · Accepted Answer

Q: 350 Motor Mounts for 1969

A: Earlier I was asking about the Motor Mounts for a 1969 350, and I told you when I found out FOR SURE I'd give you an update.

The Anchor book is WRONG. The 1969 350 does NOT use two different mounts. They use the same mount on both sides and it is the SAME mount used for 400s. I believe it is Anchor PN 2254.

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Question 2

455 Swap

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Q: 455 Swap

I have an opportunity to buy a 455 out of a bonneville. Anybody know what (if any) modifications I will need to do to get it to fit?

A: This is a very simple swap. Since 1967, all Pontiac V8s have the same external dimensions, and will readily swap parts like intake manifolds, timing chains, and oil pans. The exception is the much maligned 301.

As another list member mentioned, the Feb. 2001 issue of Car Craft has a brief article on swapping a 326 for a 455. It contains some good photos of the differences between the 1969 and earlier motor mount bosses/holes and the 1970 and later version. There is also a good description of water pump and pulley issues that need to be addressed. The article would apply to those of you with 350s and 400s as well.

But, essentially, the easiest way to do the swap is to take the timing cover, water pump, pulleys, and accessory brackets off your present engine, and transfer these to the 455. The same applies to your exhaust manifolds. Now the 455 will just bolt into place like it grew there.

Some other issues not mentioned, or only lightly covered in the article are:

-Flywheel/flex plate. While the majority of Pontiacs in the late 60s and early 70s used the same sized crank shaft flange, the late 50s and later 70s car are different. In fact, there are up to 5 different diameters in the Pontiac engine family. So, measure the rear flange on your 455 and check to make sure that your original flywheel/flex plate will bolt on, or use the one that came with the 455 if possible.

- Manifold sealing. Intake ports on Pontiac heads changed roughly about 1972, so if this engine is later than that, you'll need to get the correct gaskets to seal your intake manifold. In the Car Craft article, they used some thin metal to block off the heat passage crossover, which is the area that will most likely leak. This is assuming you will be using a 1972 or earlier intake manifold.

- Engine weight. While we don't have any exact figures on engine weights, it is logical to assume that a 455 weighs more than a 326, perhaps. You may have to get new front springs for your car if once the bigger engine is in and your front suspension bottoms out.

- Water pump/pulleys/ accessory brackets/timing covers. Pontiac in it's infinite wisdom, changed the design of these front engine dress parts several times, and mixing these parts leads to poor pulley alignment, thrown belts, and premature baldness. But to give them credit, the blocks themselves are pretty universal.

Whatever you do, use all the parts from either the donor Bonneville, or your present engine.

The 1967 and 1968 Pontiacs (as well as the earlier engines) used an 8 bolt timing cover and pump. In 1969, they went to an 11 bolt cover and pump, but had two different pump designs, each a different height. This means that the pulleys and brackets are different for each pump type. The 1967 and 1968 items have different part numbers also, and they may be incompatible as well. But I don't know for certain. That's why you'll stay sane longer if you source these parts from just one car.

- Engine mount bosses. The 1969 and earlier engine blocks were cast with two drilled and tapped bosses or holes for the engine mounts, along the oil pan mounting flange. In 1970, because many of the new cars had undergone chassis redesigns, the new blocks were cast with 5 bosses to allow the engines to be mounted in either earlier (pre 1969) or later chassis.

Some of the blocks cast in the '70s don't have all of these holes either drilled or tapped. Others do. If your 455 doesn't, it shouldn't be too hard a job to drill and tap the required holes. Use a correct engine bracket for a guide.

The other recourse is to use engine change brackets available from Year One, Performance Years, and AMES.

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Question 3

670 Heads

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Q: 670 Heads

Should I use my 670 heads or switch to something else. I have heard the 670 are closed chamber heads and the valves are shrouded. You would do better with some 62,16,12,13, or 48's.

A: While you are right about the shrouded valves, I find it interesting that Pete McCarthy writes the following in his "Pontiac Racer's & High Performance Handbook":

"The 670 heads are unique in a number of ways:

I was and is the only late closed chamber design.
The intake port is the best flowing of any production head including the Ram-Air IV.
It is the only big valve head with exhaust port air injection holes, although a number if Eastern cars didn't have them.
It was the first in a long line of high performance Pontiac heads with screw-in studs and stamped steel pushrod guide plates.

If one obtains these 670 heads, and opens the chambers ala the 1968 and later 400-428 heads, and adds the good valve prings, you will have as good a high compression head as is possible to find. The 670 head is one of the great junkyard buys available.

That's pretty impressive. I imagine that the removal of the material shrouding the valves, plus enlarging the chamber to match the better quench area of the 1968 and later heads, one would also shave a couple 10ths off the compression ratio, ending up somewhere in the are of 9.75 or 9.5 to 1. Remember that Pontiac overestimated compression, so a rated 10.5 to 1 was closer to 10 to 1.

If you were looking for a decent head to use without modifications, and found the 670s at a good price, they are worth buying. If you were interested in making the above modifications, you would end up with dynamite heads.

By chance, the 1968 YS block (GTO/big car) in my car came with these heads. After reading McCarthy's comments, I decided to hang on to them.

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Question 4

A/C Reserve Vacuum Tank

admn · Accepted Answer

Q: A/C Reserve Vacuum Tank

I have a small coffee can shaped vacuum canister that I found underneath the drivers side fender mounted to the firewall on my 1968 400 convertable. Any ideas what it is used for? Appears to have never been hooked up. The manual doesnt help.

A: It's the A/C reserve vacuum tank.

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Question 5

Accessing the #2 Plug

admn · Accepted Answer

Q: Accessing the #2 Plug

I need to know if I do, in fact, have to move the a/c compressor to get to the #2 plug.

A: I move the compressor to get to the plug. I don't know about the other guys, but I prefer using up the time to save me frustration!

A: #2 plug is easily accessed by going thru the inner fender seal (mud flap). You may want to jack up the front end and remove the tire for real easy access.

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Question 6

Adjusting Valves on a 350

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Q: Adjusting Valves on a 350

My son and I are having trouble adjusting the valves on our 350 small block. We just ported the heads (edelbrock) and tried to adjust them with a steatho scope... they have hydrolic lifters and new push rods... can't get any power out of the engine and when we crank down on the valve the noise still is there.... any ideas on how to adjust them?

A: I can't imagine of what use a stethoscope is while adjusting valves, but I'll tell you how I do it. I usually performed this with the engine running, and the valve covers off - do this one at a time since it can get a little messy. You may want to lay a piece of cardboard or small piece of scrap sheet metal across the head to contain some of the oil. Set it inside the lower lip that the gasket sits on, and do one side at a time if you want to. Back off each rocker nut until that valve ticks, tighten until the ticking stops, then tighten some more. How much more? That depends on if the lifters are new or not. If new, turn one complete turn, if old, go a half turn, if not too old, go 3/4 turn. Reinstall valve covers and clean up oil splashes with CRC Brakleen.

Some people prefer the static (engine not running) method, it also works well, but takes more time.

A: Here is a simpler method. It still works for non poly-locks. This is from Rock and Roll engineering web site.

Poly lock nut adjustment for hydraulic cams

Install poly-lock with hex end up. Thread in set screws a few turns with hollow hex end up.
Make sure lifter in on the heel of the cam.
In order to get a "feel" for the pressure of pushrod against lifter cup, push the pushrod into the lifter by hand so you can feel it's spring tension. Tighten poly lock slowly while moving the pushrod up and down, being careful to stop turning the poly-lock just as the pushrod touches the lifter cup, and the up and down free play is taken up.
Now turn the poly lock one more "flat", or a sixth of a turn. Hold the poly lock in that location with a box end wrench. Turn the inside allen set screws down until it contacts the rocker stud. Snug it with the palm of your hand. Do not tighten!
With the box end wrench in one hand and the allen wrench, turn both together until they tighten, or approximately 25 to 30 ft. Lbs. They must be tight, but you don't want to be an ape either. Use common sense.

Warning! You cannot properly tighten poly locks by just turning the allen set screw.

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Question 7

Backfiring Problem

admn · Accepted Answer

Q: Backfiring Problem

I have a 1968 Firebird with a built 73 Pontiac 350 and an electric choke. The last two mornings on the first start it has backfired. I'm a pretty weak mechanic...as you can tell. What should I do.

A: I'd start with the choke. See if the is sticking and flooding. Also, check the timing. When was your last tune-up?

A: Your problem could still be in your choke. Is it backfiring through the carb or exhaust? If through the carb, most likely you have a lean situation that could be caused by your choke not closing fully. This would explain why it goes away when it warms up. If it is your exhaust, that's another story and most likely would involve timing or a sticky exhaust valve.

The first thing I would do is check the position of the choke when cold. Before you start your car, remove the breather and open the throttle to allow the choke to close. If it doesn't snap closed fully, there's your problem. Check to see if you can close the choke all the way (there should be a slight opening about 1/8th to 1/4 inch when fully closed) by pressing it closed. If this is the case, buy a can of spray carb cleaner and hose the linkage. If the problems persist, you'll probably have to grab a buddy (or mechanic) who know a little more about old cars and get him to help.

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Question 8

California AIR System

admn · Accepted Answer

Q: California AIR System

I have a 1967 firebird with a 326ci with a 4 bbl carter carb and it had factory air. the car has a smog pump which i tried removing but the heads had holes in them that had hoses coming out and joining to some sort of object in the middle then in turn connected to the smog pump which had a hose connecting to the air filter. i tried plugging the holes in the heads but the engine would just starve for air when i tried turning the car on, and it would make a weird popping noise when i kept them unplugged could anybody help me with these problems?

A: Concerning your AIR pump. First off, let me start out by saying that the AIR system you are refering to came on California Firebirds only, and is somewhat rare. If you plan to remove it, keep it intact, and that includes the vent tube from the right rocker to the air cleaner, and the air cleaner as well. (If you are just going to toss it, let me know and I'll purchase it from you at a fair price.) You can remove the AIR system from your car and run without it. All Pontiac heads from 1967 have the holes in the heads that you are refering to. Non-AIR equiped cars have 'plugs" which are screwed into the heads. Remove the AIR pump and associated plumbing. Screw in the plugs into both heads, and plug the the inlet on the underside of the air cleaner. That's it. If the engine was starving for air, it wasn't because you plugged the AIR ports in the heads. Look for another problem. The AIR system is masking it.

Key Words: AIR, A.I.R., emissions, CARB, Air Injector Reactor

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Question 9

Cam for a 1968 400

admn · Accepted Answer

Q: Cam for a 1968 400

I'm trying to track down the stock spec's for the cam in my 1968 Firebird 400 conv. It has no performance upgrades that I am aware of, any help? Lift, duration, lobe sep, etc.

A: Actually the stock cam options for the standard 400 on 1968 birds was the 067(400 std AT and manual), 068(RA-I AT; 400HO manual), 744 (RAI-4speed) and 041 (RA II AT and manual)

Side Notes: 066 was only used on standard 1967 auto 400 firebirds. 400 std autos were 'upgraded' to the 067 cam in 1968. Interestingly, the 400 HO auto cars did not receive the cam upgrade (to 068) that the 400 HO manual cars received. Instead the auto 400 HO cars used the stock 067 cam in 1968. Also of interest, the RA I auto cars were 'downgraded' to use the 068 cam (vs the hotter 744 cam used on RA I auto birds in 1967).

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Question 10

Chevrolet Engine into a Firebird

admn · Accepted Answer

Q: Chevrolet Engine into a Firebird

I have recently bought a 1967 Firebird that rotted outside my bedroom window since I was 13. Now I am all grown up and own that car but there is no engine. It has the origional 400 transmission and I have a 1969 327 from a Vette but I am not sure it will bolt in as is. Can anyone advise?

A: It won't be a direct bolt in as Chevrolet uses a different bellhousing bolt pattern that the rest of it's corporate sisters (Buick Olds Pontiac). However, there are some relatively cheap adapters orderable from Summit, Jegs, PAW, etc, that will allow you to mate these two together.

In addition, you will need to get the motor mounts and frame brackets from a Camaro to seat the engine in the car. The matching holes should already exist in the subframe. You will also need Chevrolet accessory brackets for the power steering, alternator, smog pump, etc.

A: You'll need to get an adaptor from Summit. It's not in their catalog, you have to ask for it. It's about $65. It will allow you to connect a Chevy engine to a Pontiac trans. Then, you will have to reroute the fuel line to the passenger side instead of the driver's side. And lastly, you'll need engine mounts to fit a Camaro (most parts stores). Most anything else you run into can be easily remidied. This will get most of it. If you can get a Pontiac engine, you'll have a lot more low end torque though. Do what I'm doing, I put the chevy engine in just till I find and can afford what I really want, a 455!

A: Why not just sell the Corvette motor to a Corvette guy and buy a 400 or 455 for the bird. With the extra money you save on motor mounts,adapters,exhaust,carb linkage etc. you could even find a nice running Pontiac motor.

You dont say how mechanically inclined you are but I have a feeling that if you had to ask this question then you are already over your head as far as an engine swap. Besides your restoration will be worth more if its close to correct. If the car was a true 400 car(the only one that used a 400 trans) then I would suggest looking for a correct replacement.All of this also hinges on the condition of the car in its present state. If it is totally rotted you may want to consider another project.

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Question 11

Dealer Service Information Bulletin 68-I-14 - Viscous Fan Clutch - Improper Diagnosis

admn · Accepted Answer

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Question 12

Dipstick Problem after Rebuild  for 1967

admn · Accepted Answer

Q: Dipstick Problem after Rebuild for 1967

I just rebuilt a 326 Pontiac motor to put onto a 1967 firebird. Before I had it rebuilt the dipstick was fine like it should be. But when I got the finally put in the car and fired it up the dipstick shoot right out of the the motor. I got out of the car with it still running and started to put it back in the motor but it keeps hitting on the cam. CLICK CLICK CLICK I even order a new tube and dipstick together and put it in. I still have the same problem. I was wondering if you knew what could be the mess up? Thanks

A: I posted a similar problem on one of the performance years pontiac boards. When you replaced the tube, do you mean the external tube, accessable from the outside of the engine? Sounds to me like your inner tube is bad. You have to pull the oil pan to replace it. To do this you may have to pull the engine or if you're lucky you can just remove the distributor and jack up the engine to get it off. The lower tube inserts into the block from below. That's as much as I know since I haven't actually done this yet, I still have the click click problem unless I put in the dipstick just right.

A: Your dipstick is hitting the crankshaft and sorry to say I think that the lower portion is bent or missing. You may have to PULL the oil pan to see what is going on down there. You didnt mention if the car has A/C or not. A/C cars use a different dipstick and dipstick tube perhaps you have a short tube and a long dipstick. You can check this by putting the car on level ground and check the oil level on the dip stick. With 5 qts. in the pan you should read about 1/2 qt low on stick.

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Question 13

Distributor Vacuum Advance Valve Assy

admn · Accepted Answer

Q: Distributor Vacuum Advance Valve Assy

Was the Vacuum Advance Valve (control) only on Firebird's, or was this also on GTO's ? Was it installed on any `68 Pontiac with any manual trany ?

A: The Distributor Vacuum Advance Valve Assy was used on all 1968/1969 Pontiac's with Manual Trans and the 1967 M.T. A.I.R. engines. # 9773623. It was attached to the RH Rear of the Intake Manifold. The Plastic Cover on the end should be Black. On the RAII engines, this cover was Green (#9794257).

This should not be confused with the Distributor Vacuum Control which attached to the Distributor itself. Both are available NOS now & then.

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Question 14

Dual Diaphragm Distributor

admn · Accepted Answer

Q: Dual Diaphragm Distributor

I am having a problem with a slight backfire and someone told me to disconect one of the two hoses to the distributor. Is this correct?

A: 68 was the only year for a dual diaphragm (advance /retard) distributor. It was to retard the distributor under certain conditions for emission lowering. A service bulletin was issued for dealers that got complaints to disconnect the retard side. A lot complaints of a slight backfire on coasting downhill and deceleration . Such a tech service bulletin wouldnt be issued today as theres a stiff fine for modifying or removing any emission device Chances are the retard side has been disconnected on yours. Look for a separate vacuum hose nipple on the distributor advance/retard control "thingy".If its been removed,hope that the vacuum source has been plugged off.

From the Pontiac Service Information Bulletin:

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Question 15

Dual Port Advance for 1968

admn · Accepted Answer

Q: Dual Port Advance for 1968

My 1968 is missing the dual port advance. Is this part necessary?

A: The purpose for the dual port advance was for early emissons and with the redesign of the 1968 heads that are supposed to sacvange the fuel and air to burn cleaner.

A: Dual port advance mechanism was actually a retard and advance unit in one can. Tech bulletin I have states that some owners complained of popping in the exhaust due to the retard. Most dealers disconnected the retard and sent the customer on their merry way

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Question 16

Engine Rebuild

admn · Accepted Answer

Q: Engine Rebuild

My new 1968 firebird 400 is burning oil on start up. I think I've got some time left before she's real bad. So I'm starting my research now on rebuilding my motor. There's several issues that have come up and I would like some clarification...If you can...

1) I have been told that a chevy engine will not fit the bell mountings and that the motor I most likely have...the original...is an oldsmobile engine...is that true?

2) I'd like to rebuild myself...I found pistons, valve rods in the yearone catologe...but no gaskets, rings. Is there a better engine rebuild source out there? Will a chevy rebuild kit work?

3) If I have cylinders reamed, will I need new pistons?

4) My chilton manual say there are oversized valves available for use in bored out valve guides. Is that true...where do I get em?

5) If I add high performance cam will I need different valves and valve rods and lifters?

6) If I change pistons to lightweight, and add a high performance cam is that still stock...you can't see those items.

A: In short answer form:

1) True. Chevy uses a different bolt pattern for bell house mounting. The Pontiac uses what is called the BOP (Buick-Oldsmobile-Pontiace) bolt pattern, Cheby is ...well, Chevy. The Pontiac 400 is Pontiac specific. Not the same as any other 400 by anyone. Only Pontiac parts fit.

2) See answer 1) Check PAW Atuparts Catalogue, Summitt Auto Parts.. Check into any hot rod type magazine to locate rebuild parts. Very common stuff..

3) If you "ream" The cylindes, I assume you mean reaming the ridge at the top of the cylinder. No new pistons are required. If, however, you mean to HONE or OVERBORE the cylinders, then new pistons are needed.

4) Maybe. It depends on the cam. Each cam manufacturer has recommendations. If you stay streetable, then stockers willprobably work fine. If you want something special,....... You have to pay to play.

5) Usually, stock means stock, from the factory. If you are referring to STOCK class at the dragstrip, the sponsoring raceing organization has a set of rules that define exactly what stock is. In NHRA stock class, some aftermarket cams are still considered stock. Lightweight pistons are usually not stock. If you are referring to street or bracket racing... Well what ever is under the hood is whatever you say is under the hood. Caveat Emptor! Let the Racer beware! *smiles*

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Question 17

Engine Rebuild (Revisited)

admn · Accepted Answer

Q: Engine Rebuild (Revisited)

I'm looking for feedback/suggestions on rebuilding my 326 HO. I am restoring the car to as close to original as I can, but would like to get a few more horse power. I will be keeping the stock (points) ignition, headers are not an option, stock carter AFB 4bbl, stock intake. Given this, are there any suggestions on bore,cams, heads(port/polish), lifters ect... or should I stick with stock rebuild? would like part #'s and specs to give to machine shop. Is the extra $200 they want to balance it necessary? The shop says they will use a cadillac rear seal, will this work with no leaks? open to any ideas/critisizm.

A: As I'm sure most expert motor builders will tell you, the key to making good horsepower is to make the engine breath. Having said this and knowing your limitations on the stock exhaust and intake, there are still a couple of this you can do to give the car a little more zip...

1) Camshaft. This will be the least expensive purchase you'll make. Mainly because your going to replace it anyway. I would look for a good grind that make most of it's power at the lower rpms... say, idle to 4000. Since your motor will stat to choke down at the higher RPM due to your restrictions, a cam designed for higher RPMS will most likely reduce your engines performance. Also, consider matching the grind with the head characteristic (see #2)

2) Heads: here is where the power comes from. A mild pocket porting job on the intake bowls will help reduce the restrictions and help to obtain more flow or at least as much as the exhaust manifolds can handle.

Have the heads plained to obtain a 9.5 to 10:1 compression ratio (you may already be here since they are the original heads). This is kind of on the high side for cast heads and today's pump gas but you will be OK with premium fuel as long as you don't advance the timing too far (see 3).

Install hardened exhaust valve seats to reliably run unleaded gas.

3) Pistons: 0.030 over bore with flat tops. You'll need to calculate the total volume of the cylinder and head chamber to obtain the proper compression ratio. Too much compression means you'll have to use an av-gas or racing fuel blend to prevent detonation.

4) Block: decking the block is another way to increase the compression but may not be advisable with your current heads. I would figure out what the current compression ratio is and discuss this with a local motor builder (preferably one who builds racing motors) and then decide which way to go (decking the block vs plaining the heads).

5) Balancing: This is very gray area when considering your limitations. Balancing the components will help the motor to run smoother but at the lower RPMS the benefit are small. I would ask the mechanists to weight match the pistons and rods (use the heaviest piston on the lightest rod and vice-a-versa to get the best "overall" balance and let it go at that.

6) Cadillac Main Seal: I've never done it but it sounds like a great idea. There was a god article in the December 98 High Performance Pontiac magazine about this topic and I will try it on my next rebuild.

7) Engine Tuning: Once the motor is together, try experimenting with different jetting. You may be able to increase the jet size by a couple of notches because of the larger camshaft and better breathing heads.

8) Other stuff: There is literally no limit to what you can do to squeak out a few more horses: Hotter coil, performance points, low resistance spark plug wires, K&N air filter, high flow mufflers and exhaust, etc. Pick up a Summit or Jegs catalog and let your fingers do the walking.

If you want max HP and still have the stock look, consider having the intake and exhaust manifolds extrude honed. This is a process where they forcibly push an abrasive compound through the ports to open them up and remove restrictions. Kind of radicle but some of the limited late model racers use it to improve the flow on mandatary stock components.

Well enough from me. How about some additional tips (or rebuttals) from the rest of you guys???

A: Regarding tips for more horsepower, if youve got some money:

We went with a set of those aftermarket edelbrock heads for several reasons:

from what I understand, a well ported set of stock pontiac heads will flow about 240 cfm, while the edelbrocks flowed close to 300 right out of the box. Ported, they flowed way over 300 cfm.
Many pontiac heads flow well only to a certain level of lift, after which a larger lift cam does not help flow. The edelbrocks continued to see increases after .600 inches of lift, allowing a large roller cam.

With those things said, we had some problems all you considering this upgrade might want to hear:

Our eldelbrock torkers ports did not match with the heads, and so the manifold had to be milled. (Strange since both were new and the heads were not shaved, and the parts were made by the same company.) Although the intake would have bolted on, we would have lost some power.
since the edlebrock has the round port configuration on the exhaust, youll have to locate some factory style Ram Air IV manifolds or try to find some hedders (which is very hard) We had to settle for some hedders that were incompatible with air conditioning and power steering. We also had to cut a hole in the fender well to get one of the primaries that went outside of the frame to fit, as well as a little banging on the primaries.
if you want to run more agressive than stock ratio rockers, the heads have to be modified for valvetrain clearance.

Although all this might sound daunting, the heads were well worth it, as we made 570 dynoed hp @ 5800 rpm, with lots of good old low end pontiac torque. (576 under 5000 rpm)

Finally, DO NOT run copper head gaskets with these heads, as they may leak. Our motor had to be torn down because it had water in the oil the first time we ran it on the dyno.

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Question 18

Engine That Sat for 5 Years

admn · Accepted Answer

Q: Engine That Sat for 5 Years

What is the precedure for an engine that was rebuilt and then left sitting five years with no break in period?? It was only started at the rebuilders shop and i need to know what steps I should take to get it loosened up and ready to run. I know that the fuel system needs to be cleaned and carberator rebuilt.

A: My procedure is as follows:

- Remove all the spark plugs - Using a piece of tubing on the end of a oil pump can, get 2-3 squirts of HD 30 motor oil into each cylinder -With the spark plugs out, crank the motor and watch the oil pressure gauge. It should start to register SOME oil pressure. Do this 2-3 times, not cranking for more than a minute and allowing at least five minutes between each sequence to allow the starter to cool. If you don't have a pressure gauge, remove the valve cover and make sure oil starts to flow out of the rocker arms. - Once you are sure that oil is flowing, re-install your plugs and wires. - If your distributor was installed correctly and your points are good, the motor should fire and run. - While running, listen for any lifter noise. The rocker arm clacking should begin to quiet down as the motor comes up to temperature and the lifters pump up. - If everything goes well, all your should have to do is the final timing and dwell settings.

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Question 19

Filler Panels

admn · Accepted Answer

Q: Filler Panels

What models received the filler panels in the engine compartment?

A: As the others have said, the panels came on A/C cars and 400's. Last time I visited Fabulous Firebirds, a used parts dealer in Missouri,they had some on the shelf that just needed a little paint. (Real GM sheet metal, not fiberglass). Call Charlie at Fabulous Firebirds.....573-783-5702. Hope that helps.

Only Sprints with A/C, which was the 3.8 Litre cars in the 1967 model year. The base 68-69 OHC6 4.1 Litre engines with one-barrels and A/C would also have the panels, as my 1969 OHC6 coupe with factory A/C has.

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Question 20

Firebird Throttle Cables 1968 / 1969

admn · Accepted Answer

Q: Firebird Throttle Cables 1968 / 1969

I need help finding a throttle cable for a 1968 400. What one is correct?

A: Well, it seems there are some out there selling NOS cables as something they are not.

INFO I'VE DISCOVERED (*thanks to all who've shared*)

ORIG. GM PART NUMBERS:

9792222 1968/1969 F-6 1Bbl, F-8 2Bbl
***YELLOW TAG***
Total Length End-to-End:    19.5"
Case Length:                13.5"
(((This one is apparently still avail. from GM for approx. $25)))

9792223 1968/1969 F-6 4Bbl
***BLUE TAG***

9792224 1968/1969 F-8 4Bbl
***WHITE TAG***
Total Length End-to-End:    18.0"
Case Length:                12.5"

Now, in order to confirm all of this, it would be nice if any owner's could measure their cables/cases. This includes all of the above... 4Bbl V-8, 2Bbl, 1Bbl I have a few pictures that I'm trying to get on the Generation-1 WebSite for comparison but AOL has been a real annoyance lately in updating info. Anyhow, if the updates come through, they'll be at the following site:

http://members.aol.com/Framair/TechTips.html

Thanks again to all who've helped out on this one. Sharing this sorta information will help to educate all of us (me included) on 'Bird Parts.

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Question 21

Firewall Difference Between AC and Non AC for 1968

admn · Accepted Answer

Q: Firewall Difference Between AC and Non AC for 1968

I've been working on my 1968 Firebird. The car originally had AC, but most of the components were not reinstalled when someone swapped the 6cyl for a V8. I'm not concerned with the car being original so I'm not going to try to put AC back on it. The heater blower motor case for my car also housed the evaporator core (I think that is what it is called). I was hoping to use the much smaller heater blower motor case off of a non-AC car, but according to the Ames catalog it "won't work on any car which was originally equipped with AC". Can someone tell me what is different about the firewall between cars with and w/o AC.... or can I make the non-AC case fit on my car?

A: The holes in the firewall are different for A/C cars. The hole for the A/C is about 6" wide and 11" tall. The heater only firewall is about 14" long and 5" tall (all dimensions are very approximate). Narrow tall vs short long... so to speak.

I had a 1969 400 that someone removed the A/C box and replaced it with a standard heater. He simply took a piece of sheet metal and covered the original hole (using silicone and pop rivets and cut a new hole the shape he needed. The heater cover will bolt right up after drilling a couple of new mounting holes. He painted the firewall all the same color and overall, it didn't look too bad.

If you decide you want to do this and need the heater box and controls (different on non-A/C cars) let me know. I got a couple I'll let go CHEAP.

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Question 22

Heads (061's) for 1967

admn · Accepted Answer

Q: Heads (061's) for 1967

Anyone know what kind of compression bone stock 1967 061 400 heads will give me?? iam getting conflicting information about them, some say they are open chamberd and other are saying there not.

A: The 1967 061's are indeed an open chamber head, they are the original put out as sort of a prototype, and they are unlike any before or since. The chamber is very open, but the chamber measures out to about 72 cc's... It also has 2.11 int and 1.77 ex valves.... The down side is that it has press in studs which aren't as reliable, but you can convert them cheap, relatively. These are probably the cleanest chambered head... I asked George Hanks about this set of heads, who has personally worked with these... he said

" the #061, used on grocery getter 400s in 1967. I'm convinced that this head was the prototype for the later production open chamber heads, but the Pontiac engineers learned something on this head that they incorporated into all of the round port performance heads of the RA-II, IV, HO, and SD-455 heads. While the 061 still has the A.I.R. bosses in the exhaust ports, the chamber is the most open of any of the production heads. There is almost no ridge across the chamber, as two separate cuts were used during the machining process, and the spark plug hole is located in the highest possible portion of the chamber. In addition, the rear or squish wall of the chamber is laid back to a 60 degree angle, producing a true polyspherical chamber, with an absolute minimum of squish area. These heads have been ignored for years, primarily because they did not fit into any of the NHRA performance engines, and they had pressed in rocker studs. The A.I.R. bosses clog up the exhaust ports, and within the old non-porting rules of NHRA, nobody cared, but with some porting and screw-in studs, this head will knock your socks off. It doesn't flow any better than any other D-port head, but the conversion of fuel to cylinder pressure is just as good as the RA-IV heads."

If you get a copy of Pontiac Musclecar Performance 1955-1979 by McCarthy, it will tell you about these heads, good reference for part numbers, heads blocks, etc... 061's are also mentioned in the H.O. specialties book, "Pontiac High performance Engine design and Blueprint assembly"... That head should give you compression in the realm of 9.8-10.1 with stock pistons... I'd love to have a set of them.... I've been looking for those for about a year now..

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Question 23

Heads for 350 2-bbl Converted to 4-bbl

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Q: Heads for 350 2-bbl converted to 4-bbl

A: With regard to the original post about cam selection for a 350 2-bbl converted to 4-bbl, I would suggest the Pontiac 067 or Summit 204/214 cam which was offered by someone on the list. I would go NO HIGHER than the 204/214 for your application, since you specifically wanted low end torque and gas milage. In fact I think the Summit 204/214 is probably a great bet for your needs.

A: Well put. Pontiac engines like a wide lobe center, in the region of 110 to 114 degrees. This will give you better idle characteristics compared to a cam with simular lift and duration, but with a tighter lobe center.

In addition, the port design in Pontiac heads favor low lift figures, which is why you see the factory cams with lift figures of .406" (the exceptions are the "44" cam with .410" and "041' with .518"). Adding more lift is waste of time since the port design doesn't flow any better at higher lifts.

It is said that Malcolm McKellar, an engineer at Pontiac in the 50s and 60s believed that higher lifts reduced the reliability of the engines with higher stresses on the valve train. He felt that lower lifts, along with port designs that favored efficiency at low speeds woul still make good power, but not at the price of valve train failure.

That, and the restricive exhaust ports demanded a balance between the intake and exhaust side.

As Steve suggests, either go with a Pontiac high performance grind, or an aftermarket cam that is very close. And read the Jim Hand information. He is the guru of Pontiacs, and he's done all of the testing and experimentation for us.

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Question 24

Kick Down Switch

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Q: Kick Down Switch

Where did you get this switch? I'll have to double check, but I'm almost positive that mine is missing... and will need that with my 455! Just wondering where I can find it?

A: The part is by BandM, Summit part no. BMM-20297. It's listed on page 159 of Summit's catalog that was good through June 30, but you'll have to check the web for a picture. Just search with that part number at http://www.summitracing.com.

The kit is intended to be used with an existing TH350 bracket when you swap in a TH400. I already had a TH400 and no bracket at all, so I had to fab a mounting bracket and a small piece to attach it to the throttle. Not tough if you're handy with tools. The linkage is adjustable and very forgiving for differences in mounting methods.

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Question 25

Low Oil Light on New Engine

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Q: Low Oil Light on New Engine

Just started the new motor in my 1968 bird. I am running a grind cam, hydraulic lifters, and a summit cheapy oil gauge. I have two problems. 1 there are 2 collapsed lifters that never pump up, and low oil pressure at idle (if the gauge is good).

1. Would a bad lifter cause low oil pressure? or vice versa? 2. What else could I have done wrong on the assembly? are there any oil plugs that I don't know about?

A: I don't know if this is your problem but it is one thing to look for from my experience. I put a new cam in my 350. After this I had verrrrry low oil pressure (5 PSI at idle) for about 300 miles. I talked a guy at my local speed shop and he said that I probably scratched a cam bearing when I installed it (which I probably did because I did not use an installation tool like one should). He also said that after break in the oil pressure should come back. He was right. The car is now running good oil pressure.

I'm by far not an expert but I don't think a collapsed lifter would cause low oil pressure but I'd think that low oil pressure could cause a collapsed lifter.

I can't think of any oil plugs or anything else that could cause low pressure. My guess is that you have a scratched cam bearing.

A: Your lifters may not be bad. They may not have been properly primed before you installed them. Before you disassemble your motor try this:

1) Completely loosen your non-oiling rockers
2) Use the push rods like a straw and with a pump style oil can, fill the push rod with oil.
3) Oil the rocker and reassemble then adjust your lash (do not torque them down at this point).
4) Start your motor and allow it to run.
5) If the lifters are OK it should start to pump oil (if the rockers clatter, adjust until quiet).
6) As the motor warms the rocker will start to clatter, adjust until the clatter stops.
7) repeat step (6) until the stud nut bottoms out.
8) Re-torque to 20 ft-lbs.

This worked for me when I had a couple of non-oiling lifters on a stored motor. Good luck.

A: I had the same problem and discovered that the oil gallery plugs had been removed when the block was cleaned. There are two behind the timing chain cover at the end of the lifter galleries and one in the at the back of the block. The rear plug is a screw in type located behind an expansion plug. The condition described exactly matches the problem I had once I had discovered/installed the front plugs, but not the rear. The engine would run, but the last two lifters just would not pump up.

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Question 26

Motor Mounts Left vs. Right

admn · Accepted Answer

Q: Motor Mounts Left vs. Right

There is a difference between left and right motor mounts. I don't think that Ponchos used different mount for small or big block, but I know that Chevy does use different mounts for small and big block in the 1st gen. Cramo.

A: Whats a small block Pontiac??? An Iron Duke 2.5??? Sorry but it makes my skin crawl when i hear "small block Pontiac" All V-8 blocks were the same size from 55-79 there were a couple of variations like short deck 303,or low deck 301 but they all have the same basic block configration. Therefore there are no small block Pontiacs.

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Question 27

New Engine Break-in

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Q: New Engine Break-in

I just got my Firebird back out after rebuilding it. It's awesome when it idles you can hear the cam. If I'm cruizin at 30mph and I put my foot all the way on it - the tire spins. If I get on it from a stand still it spins all the way from first into 3rd. It dont let up till I do.

A: Thats not the way I would breakin a fresh motor. Have you changed your oil & filter yet?

Heres what i do: - Run engine for 30 minutes high steady idle to breakin cam - Drain oil and change filter, run 500 miles using new car breakin rules. - Change oil and filter again. - First few miles should be a light throttle then coast light throttle then coast.

This process will help in seating rings. NO full throttle blasts.... I know its tempting but its proven that the infancy of a fresh engine will pretty much determine its life. Have fun and make it last.

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Question 28

Oil Dipstick Tubes For the 1968 400

admn · Accepted Answer

Q: Oil Dipstick Tubes For the 1968 400

What is the correct tube for a 400?

A: After some research into the question of oil dip stick tubes for the 400 firebird I found that it has three tubes.

The first is in the oil pan, the block to baffle tube, a short curved piece about five inches long and copper in color. The second is about nine inches long and ever so slightly curved, which extends from the outside of the block to the third and final section. Lastly, the third tube runs up from the end second tube to where it itself ends, just above the rocker cover. The dip stick itself is inserted and held into the third tube, which has a small bracket that attaches to the front outside rocker cover bolt. The GM numbers for these are as follows: block to baffle #546281 9" curved (GM calls it straight) #9795830 upper #480843

I was able to purchase all but the upper of these at my local pontiac dealer. That one they stocked, but were temporarily out of.

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Question 29

Oil Filter Replacement

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Q: Oil Filter Replacement

The part catalogs do not go back far enough anymore and I did not write down the number I needed. Does anyone know what is the correct replacement for our oil filters?

A: Use A/C filters PF-24.

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Question 30

Oil Pressure is Low

admn · Accepted Answer

Q: Oil Pressure is Low

I just rebuilt my engine and installed a new mechanical oil pressure gauge. It shows I am running with very low oil pressure. Can I still drive it to break it in and hopefully solve the oil pressure problem on its own?

A: First off... this is your motor and your money so you need to do what's best. Running a motor with low or no oil pressure is VERY damaging. This is only a suggestion for something to check. ..

You mentioned it's a new mechanical gauge. Is there a lot of air in the line? If so, lower pressures may not register until you sufficently compess the air... i.e., "Pressure about 60 lbs at 3500 rpm estimated". Try bleeding the line to remove the air.

Once you have established you have oil pressure at idle the next suggestion applies... It's not uncommon for new motors to have problems getting oil to the rockers. If the lifters were not primed properly they will not pump. Here is something that worked for me. Loosen the rockers and slid them to the side. Use a pump can with oil and fill the pushrod. Slid the rocker back and tighten until you cannot twist it between your fingers. Do not torque them.

Once all the pre-oiling is completed, start the motor and see it they start pumping. Thighten until they stop clattering -- one at a time in 1/4 turn increments. If they are still pumping, keep tightening. Once you bottom out, you can torque the nut. Be aware that this is VERY messy. I used cardboard to fill the gap between the head and fender and fender covers to keep it off my car as much as possible.

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Question 31

Oil Recommendation

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Q: Oil Recommendation

What oil is recommended for my 1968 engine.

A: My 1968 owner's manual says that non detergent oils are specifically not recommended. It recommends the following SAE Viscosity Numbers:

Above Freezing (32deg.F.)..................... 20W or 10W-30 Below Freezing (32deg.F. and above 0deg.F.) ...10W or 10W-30 Below 0deg.F...................................5W or 5W-20

All high output (H.O.) engines require the use of SAE #30 oil in the summer (above 32deg.F.) and SAE 5W-20 oil in the winter (below32deg. F.)

SAE 5W and 5W-20 oils are not recommended for sustained high speed driving.
SAE 30 and SAE 20W-40 oils may be used at temperatures above 90deg.F.
SAE 5W-30 oils may be used at temperatures below 32deg.F.
SAE 10W-40 oils may be used at temperatures between 0 and 90deg.F

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Question 32

Oil Spraying Out of Dipstick

admn · Accepted Answer

Q: Oil Spraying Out of Dipstick

I just recently purchased a 1967 bird with a 400 and an automatic tranny. It needs some work but for the most part is all original. The motor has 670 heads and is a YT.

The engine seems to have a lot of power but when I rev it very high I get oil thrown out of the dipstick tube onto my exhaust manifolds. I suspect the bottom end of the tube is missing or the windage? tray is not installed. I am the third owner of the car. The second owner told me that the engine had been rebuilt. Bored .40 and bigger cam installed, heads have been redone.

A: Oil spray out of the dipstick tube could mean excessive blow-by (i.e., the rings are gone or broken ring). Run a compression check before you break the motor down.

A: I had the same problem when I installed after market valve covers. I was waiting delivery on a oil breather, and since I had just installed headers and a RPM performer manifold I didnt want to wait for it, so I just blocked the cover off and took it out for a run. Guess what, oil shot out the dipstick due to back pressure. Suggestion to original question. Make sure there is a clean unblocked breather on one of the valve covers.

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Question 33

Original Oil Filter

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Q: Original Oil Filter

Wanted to know if anyone knew anything about PF23 AC oil filters. I ran across a NOS one that is white with blue stripes and red AC logo on it. On the box the only application listed is 1967 Pontiac V-8. I am sure it was superceded by the PF24. The 1967 Firebird parts manual supplement that is dated effective February 1967 lists only the PF24, the 72 Pontiac master parts catalog lists all PF24, no PF23 for anything. What would be correct for a 1967 bird built third week in May if it just rolled off the assembly line????

A: Just curious as to why you want an original oil filter, be it a PF-23 or PF-24. To be 100% correct as it was at the showroom fresh off the assembly line it would be painted PMD metallic blue. The AC identity would be obscured. There are lots of reproduction AC filters out there. Go to K Mart buy the latest AC filter and paint it PMD metallic blue. I wouldnt run an 30 year old design filter on a $20K restored car anyway. No more than using 30 year old oil. Just trying to save an engine an some money.

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Question 34

PCV Purpose

admn · Accepted Answer

Q: PCV Purpose

Is the PCV valve required for crankcase ventilation if I have a breather in my valve cover?

A: The purpose of the PCV is to ventilate the crankcase of by-pass gases and while helping to prevent any positive pressure buildup which will blow oil past seals and out your dip-stick tube. These gases contribute to oil breakdown and internal varnishing. Using your intake vacuum as a source, the gases are "pulled" from the crankcase. Just having a vented breather is not enough to properly ventilate the crankcase.

Q: Ok so I have to have the PCV valve (I was hoping you would say I didn't!) Does it have to be located in the valley pan or can it be in the valve cover? I bought a replacement valley pan made out of rolled aluminum and it doesn't have a hole for the pcv valve. Also. isnt the PCV valve a piece of smog equipment? What did early cars say from the 50's have for crankcase ventilation?

A: Installing one in the valve cover will work fine. Before PCV valves, most motors had an open vent tube coming from the lifter galley. Typical on early SBC was a vent pipe the attached behind the distributor to the block. The other end had a "baffle" at the back of the lifter galley. On a weak motor, you could see the blue smoke coming out of the vent tube under the car. Imagine the smell! And by the way... another reason the have a PCV valve is to help reduce engine blow-by odors and fumes inside the car.

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Question 35

Removing Engine

admn · Accepted Answer

Q: Removing Engine

I now have a question. Am I going to be able to pull the motor without also removing the trans or should I remove the motor and the trans toghether? Or, better yet, what is the easiest way to get the motor out? Now please remember, I am a rookie at this. This will be my first engine removal.

A: In my opinion it's easier to remove the motor with the trans all at once. Just remove the trans cross member, radiator and the distributor and you'll be ok. The fan makes it kinda tight but it should come out without taking it off.

NOTE: Make sure that you mark the position of the rotor when removing the distributor and make sure that you don't turn the engine after you've removed it. If you do turn it then you will have to find TDC on cyl. #1 and set the distributor to that. Just put the distributor back in after removing the engine if possible.

I used one of those plates that bolts up to the intake manifold and used the rear lifting hole with the cherry picker. You may want to use one of those lifting bars that has a handle and allows you to shift the center of the lift. The only issue is that you need to use chains bolted to the front and rear of the engine for that (no biggie but ....).

Put blankets or other things on your fenders to protect them from getting scratched or bangged up.

A: I pulled mine in one piece - engine and tranny. But I did have the front end off of mine. I would recommend removing it anyway, if you're doing compartment detailing. It comes off in about an hour. Unplug the lights, remove the radiator-to-fender gussets, unbolt the hood latch-to-radiator, four bumper support bolts and it comes off in one big piece. The core support is held in by four bolts.

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Question 36

Runs Great then Quits

admn · Accepted Answer

Q: Runs Great then Quits

My problem is my 1968 - 350 runs great in the garage but stops on me under power or extended road work. It can go for days without shutting down and then when I think the problems solved, wham! The motor will sometimes start right back up (sometimes rolling in neutral) or I may have to wait five to twenty minutes. This has been happening for six weeks. I have tested or replaced the following.

Fuel pump, flex lines, Carb. Note: No residue in carb fuel line filter
Complete tune-up with points, condenser, rotor, cap, wires & coil.

Note: Dwell & timing stay perfect. Anyone out there with an idea.

A: It sounds like you've been guessing instead of diagnosing. The next time it quits and stays dead, check for fuel and ignition. If fuel, it may be vapor locking in the steel line, or a fuel pump that's weak. Could also be a problem with the tank, maybe there's not enough venting, causing the tank to have a vacuum in it preventing the fuel pressure from being maintained. Ignition is likely to be a bit easier to troubleshoot, unless it's something weird like a loose wire in the ignition circuit or such.

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Question 37

Severe Miss When Cold

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Q: Severe Miss When Cold

I'm trying to track down a miss during warm up on my bird. In the past, I could start the car when cold and drive away, it would run fine. I've noticed a miss that has progressively gotten worse after each day, spanning over the past months. I've replaced the distributor cap, rotor, plugs and points but no change. The car starts fine, but it randomly misses, getting better when it warms up. Once at operating temp, it seems to run fine but you can hear it miss a little randomly. Under heavy acceleration there is no stalling of performance, hot or cold. I doubt it's the carburetor (Edlebrock 650) because the car seems to run fine after warm-up, just a random miss.

One thing. The timing is set really advanced, about 14 degrees BTC. I've been running it that way for a number of years. If I set it to 9 degrees there is no power. Also, the manifold vacuum is 18 and steady when hot.

Any tips on what to look for would be helpful.

A: check for vacuum leaks check or replace plug wires replace fuel filter

A: I suspect you don't have enough choke action. Either insufficient spring tension, sticky linkage, or too much choke pull-off. Generally lean when cold. If you set the timing back it would probably pop back through the carb with all else the same indicating it's lean.

A: Change the plug wires. The wires are more than likey breaking down when cold since more current is needed then. A good set of Delco wires should do the trick.

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Question 38

Sluggish Motor

admn · Accepted Answer

Q: Sluggish Motor

I am experiencing a problem with my motor running sluggish. While accelerating it runs fine but when you ease off to a cruising or constant speed, it seems as if it is missing and surging. I have replaced plugs, wires, points and condensor, and even taken the carb off and made sure there is no vaccum leak to the manifold. I am stuck! The only thing that I remotely have left is the distributor. Could this be the problem? Has anyone experienced anything like this? I appreciate any help.

A: Two things come to mind.First if there is excessive ignition advance it can cause the problem you describe.To find out,try disconnecting the vauum advance hose and plugging it then test drive the car.If it is now O.K. check the initial timing, amount of centrifugal advance and amount of vacuum advance.It is unusual but I have seen the internal limit "stop" in the vacuum advance can break allowing the rod to move way too far.You will need a vacuum pump and a "dial-back" timing light to do this check.The other thing is if it is running too lean a fuel mixture at cruise it will cause a surging condition (it would be better under acceleration due to the power system) This is a little trickier to test for.The easiest way would be with a gas analyzer which the average person doesn't have access.A crude way of finding out is remove the air cleaner and plug and vacuum hoses removed then run the engine at 2000-2500 rpm (engine must be warmed up and choke fully off) Now partially resrict the air horn either with your hand or by partly closing the choke valve and see if the rpm increases.If the rpm picks up sharply and the motor sounds smoother you likely have too lean a mixture.The reason may be a number of things which I could only guess at with out more info.This test is admittedly a bit crude and requires a bit of experience to interpret the results of.

A: If your car has a Quadrajet, your throttle slide (the little brass cylinder that pulls your metering rods up and down) may be sticking. This happened on a 350 I had. Try pulling the top off of the carb and us a Scotchbrite pad to buff it up and see if that helps.

A: I found the problem with the motor surging on my bird. I pulled the distributor and found a wire to be dangling off of the vaccuum advance module. I dont know what purpose this wire served but one end had a screw which held it onto the module itself and the other end was bare just laying in the bottom of the distributor. I went to a local salvage yard and picked up an HEI distributor for 20 bucks and installed that in the car. (Much better than points system). Didn't even have to beat the firewall in, went right in. I am soooo relieved. I was starting to think it was something mechanical. I thank everyone for the help you have given me.

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Question 39

Small Block Chevy in a 1968

admn · Accepted Answer

Q: Small Block Chevy in a 1968

I've just been offered a hard to refuse buy on a almost new custom built Chevy 350, 350 HP street engine (trust me - for the price you would consider it too). My '68s 2 bbl is tired and needs a rebuild. The engine currently in the car is correct Pontiac but not numbers matching, nor is the transmission (I don't have either of the originals). So I'm thinking about putting in the Chevy. I know some of you have done this, so what's you're experience? What do I have to do to make it work?

A: Given that the Firebird chassis shares so much with the Camaro, an SBC goes in quite easily. You need the following:

- Camaro engine frame mounts. Easily found at any source that sells Camaro stuff. Classic Industries, National Parts Depot, Year One, etc. Plus the rubber/steel engine mounts.

- Accessory mounts. You need Chevy brackets for the power steering, alternator, and A/C if so equipped (can't remember if your car is so equipped).

- Accelerator stuff. This gets a bit tricky. The 1967-1969 Camaros used a rod linkage for the throttle, as did the 1967 Firebirds. The 1968 and 1969 Firebirds and other Pontiacs were ahead of the pace by using cable linkages. You need to change your linkage to the Camaro variety, which should utilize the existing holes in your firewall. You may need a Camaro or 1967 Firebird gas pedal assembly. I know where you're likely to find one if needed. You also need whatever throttle/kickdown brackets are appropriate for the linkage and carb you will be using.

- Fuel line. The Firebird hard line comes up along the subframe from the the tank on the right (passenger) side of the car, then crosses over to the left side along the main front crossmember. The Camaro unit ends just past the crossmember on the right side. You will need to either cut your line, or replace it with the Camaro piece. Cutting the line will of course, make it more difficult to go back to a Pontiac engine.

That should do it.

Now, with some searching, I can imagine you should be able to find a recently rebuild or at least good running Pontiac 400, 428, or even 455 for fairly cheap. Probably not as cheap as the Chevy engine you found, but reasonable. Heck, you might even consider a reman. engine from one of the discount parts houses in the area. Pepboys, Kragens, etc.

Of course, you know I had to add this option. While I'm not a purist, I still dig Pontiacs with Pontiac engines. And your car is too cool to wear a bowtie. And I even own a bowtie car!

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Question 40

Spark Plugs on 1968 - #8 Plug Inaccessible

admn · Accepted Answer

Q: Spark Plugs on 1968 - #8 Plug Inaccessible

I have a 1968 400 with A/C and have never been able to contort my arm just right to get the number 8 plug out because of the close quarters to the A/C. I've had to take it to a shop to put it on a lift to get at it from below and even then, the mechanics bitch about it. A couple have said they didn't think it should be that tough and my engine mounts may be off kilter, but they don't know enough about Firebirds to know for sure. Anyone else have this problem? Anyone have the measurements I need to verify if my engine is sitting in the right place in the bay? Anyone have any tricks to getting at that #8 plug, I've tried everything (from top, from below, through the wheel well) and always end up cursing the thing out.

A: I have had the same problem on my 1968/350 with air. I have been able to get it out using a spark plug socket and turning the socket with an open end wrench. I have to do it by laying under the car. My arms usually go numb three of four times during this operation from the cramped quarters and working over my head. It is a major pain to get out.

A: The best plan of attack is to remove the rf wheel and go in through the wheel well.Snap On tools makes a 3/8 drive ratchet in a 1/4 body that works great for stuff like this.I have worn mine out 3 different times from using it so much on the new cars of today. Break the plug loose with a wrench on a short plug socket (they are all not the same) and then use the ratchet to take it out until you can turn the plug with your fingers.

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Question 41

Speedo Cable

admn · Accepted Answer

Q: Speedo Cable

Anyone knew how to disassemble the 1968 AT cable from the casing. I've tried pulling the cable out from the speedometer head side but no luck. Does it come out from the transmission side?

A: My Speedo cable broke a couple of years ago and I pulled it out from the top behind the cluster. I didn't move the casing of course, just the cable. I also reinstalled a new replacement cable thru the cluster top down to the trans. (Also make sure you oil or grease the cable for smooth gage readings.)

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Question 42

Speedo Cable Lubrication

admn · Accepted Answer

Q: Speedo Cable Lubrication

Does anyone of you guys know how to fix my nervous speedo dial? Driving slow or fast doesn't matter I can't get a steady reading.

A: Many times nervous needle is caused by a dry speedometer cable. Try pulling and lubing the inner cable with quality speedo lube and reinstalling. This has fixed my needle problems on 3 different cars. Just looking at a part of a restoration that is sometimes overlooked, and a cable breaking because it is dry is no fun either.

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Question 43

Thermostatic Vacuum Switch (TVS)

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Q: Thermostatic Vacuum Switch (TVS)

My 1968 400 Firebird has what I believe to be a vacuum switch on the intake manifold and there is at present nothing connected to it. Should there be? One would think there should. I have no idea what to hook up to it as all of my vacuum lines seem to be accounted for. Any helpful suggestions would be greatly appreciated.

A: Yes, it should be there. Should it be hooked up? If you want it totally stock yes. Is it necessary? Probably not, especially if someone has replaced the vacuum advance unit (regulating vacuum to the distributor) on your distributor and you don't have a dual port unit anymore.

If you did want to hook it up, there should be five ports and they go something like this, I think:

Inputs: Carb Advance, Carb Retard, Manifold Vacuum Outputs: Distributor Advance, Distributor Retard

If you want to hook it up and be sure, get the vacuum line kit from AMES and ask them for directions (if they don't come with it).

A: It is what's known as a thermovacuum switch.When the engine coolant temp is below the temperature rating of the switch certain ports are open to each other allowing vacuum to flow between them.Once the temp rating is exceeded the thermal pellet raises a rod inside & switches the vacuum to different port(s).This switch works very much like a thermostat.They are used for many different purposes on cars,in some cases they delay operation of some device (an EGR valve for example) until operating temperature is reached (to avoid stumbling & "sag"),other times they are used to operate a device only until operating temperature is reached (example- a vacuum operated heat-riser valve).

A: Here is the text of an article that AME's FAX'd me. Looks like it was from Pontiac Enthusiast magazine (Vol. 1 No. 2) and was written by Peter Serio:

Back when emissions systems first appeared on cars, it was almost an instant reaction to open the hood and say, "Who needs this stuff to slow my car down? Let's rip it out, plug the holes, and go faster!" Years later, it may become mandatory for vehicles manufactured in the early days of emissions systems to have fully functional systems in place. In addition, in concours competition, a deciding factor can be a detailed engine compartment with a correct and operational set of emissions parts. In addition, your car's drivability could depend on an understanding of how the emissions gear works. In the previous issue of Pontiac Enthusiast, we looked at the 1968-69 manual transmission vacuum advance valve. In the next issue, I will cover the transmission-controlled spark systems used from 1970-72. For now, it's time to turn to the TVS, or thermostatic vacuum switch.

The TVS-GM#3016754 is used on all 1968 V8's and on 1969 V8's with automatic transmissions. Also, several early production 1969 Ram Air III cars with manual transmissions were built using the TVS and the vacuum advance valve. The 1971 455 HO engine also used the TVS with either transmission.

In all applications, the TVS serves as a safety device to help prevent overheating. The switch is located at the front of the intake manifold, threaded into the coolant passage. There positions inside the TVS related to coolant temperature. Standard vacuum flow is ported vacuum from the carburetor to the distributor vacuum advance. Whenever the engine coolant temperature rises above 230 degrees F, the TVS switches the distributor advance from ported to full manifold vacuum. This advances the timing about 20 degrees at idle, allowing the engine to cool down to normal operating temperature. After the engine cools, the system returns to ported vacuum.

If your car does not have the system hooked up properly, it could overheat on a hot day when you're stuck in traffic, which could reduce the life of your engine. In 1968 the fan shroud become standard for the GTO, whereas in earlier years it was an option on non-air cars. With the idle retarded in 1968 to reduce idle speed emissions, the switch's purpose was to advance the timing when necessary to allow the motor to cool down, to prevent pinging.

A manifold connector in the vacuum hose harness to the TVS is used to prevent the hoses from being installed improperly. Note that some of the vacuum hoses in the harness have color-coded stripes running on the supply lines to the TVS. The red-striped hose is manifold vacuum, and the ported vacuum is routed through a small steel pipe forward of the carburetor. The yellow hose (used in 1968 only) is the retard-at-idle-speed vacuum supply.

There were two different hose harness assemblies used, depending on the year of the car. In 1968 only, with the dual-port vacuum-advance unit attached to the distributor, the idle speed timing is retarded 10 degrees to reduce emissions. After the 1968 models, all distributor-advance units were the standard single-hose-connection style. All the '68s use the 5-hose vacuum harness, while the 1969 V8's and '71 455 HO make use of the 3-hose type. The two extra hoses on the '68-only harness are the idle-speed retard feature.

Apparently it did not take long for dealers to receive complaints that some of the 1968 cars idled poorly, and Service Bulletins 68-T-2 (dated 10/16/67) and 68-T-2A (dated 1/4/68) were released. Models affected were the 1968 Firebird, full-size, and Tempest/LeMans/GTO with the 2-barrel carb and automatic trans, plus full-size automatics with the 4-barrel. The complaint was that the second-to-first downshift could clunk badly due to the retarded timing. Manual-transmission cars were unaffected, since the idle speed was higher and you shift your own gears. The procedure outlined in the bulletins basically involves removing the two vacuum hoses that retard the timing at idle; shortening one and connecting it to the two switch holes in a U to keep dirt out of the holes; and readjusting the idle speed. If you have a 1968 2-barrel automatic or full-size 4-barrel automatic, these Service Bulletins would be a nice item to search for.

A:

  ________
 /        \
|  (1)     \
|           \
|        (4) |
|            |
| (2)        |
|            |
|        (5) |
|            /
| (3)       /
\_________ /

(1) To vacuum port on front of carb (steel routed line)
(2) To "Tee" at rear of carb
(3) To distributor advance
(4 and 5) are looped together at switch.

A:
From the 1968 Diagnostic Manual:
Fig 6D-9 Components of Controlled Combustion System
[pdfjs-viewer url=/files/FAQ/docs/6D-9.pdf viewer_height=800px fullscreen=true download=false print=true]
Fig 6D-10 Distributor Vacuum Layout V-8 2 Bbl.
[pdfjs-viewer url=/files/FAQ/docs/6D-10.pdf viewer_height=800px fullscreen=true download=false print=true]
Fig 6D-11 Distributor Vacuum Layout V-8 4 Bbl.
[pdfjs-viewer url=/files/FAQ/docs/6D-11.pdf viewer_height=800px fullscreen=true download=false print=true]
Fig 6D-12 Vacuum Routing Chart
[pdfjs-viewer url=/files/FAQ/docs/6D-12.pdf viewer_height=800px fullscreen=true download=false print=true]
Fig 6D-13 Vacuum Routing Chart
[pdfjs-viewer url=/files/FAQ/docs/6D-13.pdf viewer_height=800px fullscreen=true download=false print=true]
Fig 6D-14 Vacuum Routing Chart
[pdfjs-viewer url=/files/FAQ/docs/6D-14.pdf viewer_height=800px fullscreen=true download=false print=true]

A: Jim, a list member from the First Generation Firebird-L Mailing List, did research on this compairing all the documents available and put together his findings:
[pdfjs-viewer url=/files/FAQ/docs/TVS/68VacuumDialog.pdf viewer_height=800px fullscreen=true download=false print=true]

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Question 44

Throttle and Kickdown Hookup for 1969

admn · Accepted Answer

Q: Throttle and Kickdown Hookup for 1969

Anyone happen to have a picture of how the throttle and kickdown cables hookup to the bracket and the Carb Lever for a 1969 4bbl with TH350? How about a good description? I'm pretty sure I have the throttle cable right but I'm not quite sure how the TH350 kickdown cable hooks up.

A: The kickdown cable snaps into a square hole on the carburetor side of the throttle bracket. If you don't have the exact bracket you will have to improvise. A 2bbl one will not work, the cable will be 3/4" short of the carburetor bracket. The reproduced ones for $80+ are for 1968 and don't have the necessary square hole for a TH350. If you find a source for a four barrel cable mounted throttle bracket with the TH350 kickdown hole, let me know.

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Question 45

Throttle Cable Bracket Codes for 1969

admn · Accepted Answer

Q: Throttle Cable Bracket Codes for 1969

I just bought that bracket off eBay and think it may be the wrong one. It appears to have an F2 on it and someone told me he thinks the 1969 firebird 4 bbls have an F4 on em. Is there a difference for automatic or sticks?

A: The Throttle Cable Bracket fromE-Bay Auction is for a 1969 Firebird 2Bbl application. The "F2" designates 2bbl. The correct Bracket for a 1969 Firebird 4Bbl is 9797415 which is stamped with "F4" (for 4Bbl).

Since we're on the subject, sometime in May of 1968, a new Intake Manifold and Throttle Cable Bracket for the 4Bbl Firebird came into production.

Intake manifold: 9794234 Throttle Cable Bracket: 9797415 (F4)

This Manifold was used on late model 1968 Firebirds, GTOs, Full Size models with 4bbl Carbs. Also used on all 1969 models with 4Bbl.

This set-up superseded the previous manifold/bracket... 1968 Firebird (1st Type up until May of 1968)

Intake Manifold: 9790140 Throttle Cable Bracket: 9792242

I believe that the Throttle Cable Bracket you're looking for has been reproduced.

There is no difference in Throttle Cable Brackets for Automatic/Manual Trans.

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Question 46

Throttle Cable Bracket Replacement

admn · Accepted Answer

Q: Throttle Cable Bracket Replacement

I am changing out the intake manifold and the carb on my 1968 bird and it seems that the throttle bracket would have to be replaced. The intake is an Edlebrock Performer and the carb is an Edlebrock 600 cfm non egr carb... the stock carb is a 2bbl. i wanted to know if anyone has fit one of these carbs on their bird, and what kind of throttle bracket they used. The stock bracket seems to short.

A: I just did the exact same thing. I installed the Edelbrock Pontiac Performer and the Edelbrock 600cfm carb. I did not have the old original throttle bracket to begin with; just some old homemade bracket that was used on the Holley carb previously on there. The Holley throttle linkage sat much lower and I could not reuse the "homemade" bracket with the new Edelbrock carb.

What Edelbrock tech support says to do (after I was on hold for 15 minutes) is not quite the right thing to do. They say you need to purchase their Throttle Bracket--Pontiac ('68-'71) P/N #8015 . When you order this and get this, it has instructions telling you how to modify your old original throttle bracket!! Drill here, bend here....NONSENSE! It looks funny AND I did not have one. Besides, the original throttle bracket goes for $75 at Ames! I could NOT BELIEVE that they did not have a universal throttle bracket solution to their own manifold/carb combination!!!

The answer is to order a Lokar (brand) steel braided 24" throttle cable and throttle cable bracket (sold seperately). It goes in nice and easy and looks ever so sweet! The Lokar throttle bracket comes with dual throttle return springs. All of it is stainless steel. I found it locally but I believe that Summit Racing sells the same thing.

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Question 47

Throttle Kickdown Switch for 1968

admn · Accepted Answer

Q: Throttle Kickdown Switch for 1968

Can someone provide me with the GM part number for the kickdown switch for a 1968 coupe 400/TH400?

A: the part number for the kickdown switch is:

#9785545 (same.... 65-66 P/8 M-40, 1967, 1968, and 1969 F/8 M-40)

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Question 48

Throttle Problem

admn · Accepted Answer

Q: Throttle Problem

I recently purchased a 1968 Firebird 400. The car seemed to be a dog compared to the other 1968 Firebirds and GTOs I have owned in the past. After doing all the usual tune up tricks I noticed that my accelerator pedal only throws the throttle open half way before hitting the carpet!

I looked for an adjustment to compensate for the restricted pedal movement or a way to remove the carpet but neither seemed to have an obvious answer. Has anyone else experienced this?

A: If the carb has ever had really strong spring installed, it very well could have bent the inside linkage. My GTO had this happen. I bent it back and welded on a brace so it wouldn't happen again. Also, didn't the Firebirds 400's have some sort of throttle stop to keep from getting full throttle in order to "lower" the horsepower. That might be when the linkage got bent originally. Someone tried to stomp the pedal to the floor, it hit up against the throttle stop and bent the inside linkage. Just a theory.

A: After a closer look I discovered that the reason my accelerator pedal was only throwing the carb half open was that the mounting bracket for the pedal was cracked in two.

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Question 49

Timing Adjustment to Fix Overheating Problems

admn · Accepted Answer

Q: Timing Adjustment to Fix Overheating Problems

What are the steps in adjusting my timing to fix the overheating problem.

A: Here's the deal on timing, back to basics.

First, disconnect and block off your vacuum source to the vacuum advance. Its ONLY purpose is to increase gas milage. Next, if you keep your engine at or below 800 RPM you will have no mechanical advance. So now the only timing is due to INITIAL timing. Let's say you set the spark right at TDC, the flame takes so time to form at "explode" so the force of the explosion happens AFTER TDC, piston is already on its way down, you don't get much power. So you ADVANCE the timing to whatever gives you the best performance, which is usually between 7-12 degrees BTDC. If you have too much timing and the spark happens too far before the piston reaches TDC, then the force is pushing against the direction the piston is moving and you get detonation or knock. This is BAAAAAD.

As your engine RPM's increase, the amount of TIME it takes for the engine to turn say 30 degrees is much faster than at idle, but the TIME is take the flame to burst hasn't changed. So the timing is increased further by the MECHANICAL advance. Usually adding up to 20-25 degrees of advance to the INTIAL timing, for a TOTAL timing of 32-38 degrees.

Finally, vacuum advance was added for the purpose of further increasing timing at cruise. Most times it is connected to a ported vacuum sorce. This source has NO vacuum at idle, the most slightly off idle and then decreases to zero again at Wide Open Trottle (WOT). When cruising you can add an additional 15 degrees or more of vacuum advance, bringing your timing up to 55-60 degrees BTDC. This is the one to be careful of, too much and you can get detonation. Always stick to the low side to avoid detonation. Remember, it's just for gas milage.

One more thing to touch on. Manifold vacuum is maximum AT IDLE. All other times it acts just like Ported. If you hook your vacuum advance to manifold vacuum you will have 8-12 intial plus 15 or so vacuum for 23-27 degrees BTDC of timing AT IDLE. This will affect temp, though I'm not sure which way. I DO know, that most 1st gen birds came with a TEMP activated switch which actually switched the vacuum advance soure depending on the engine temp in order to keep it cool! The was specifically for long periods at idle.

Now, lets say your car is set up this way but you SET the timing to 12 degrees WITH the vacuum advance hooked up to manifold vacuum. That vacuum advance can is giving you 15 degrees or more of advance. That would mean your REAL INTIAL timing (without the vacuum advance) would be 3 degrees AFTER TDC, which is way to far retarded.

Bottom line, turn off the vacuum advance until you figure out the heating problem. Its ONLY purpose is to improve gas milage. Set the INITIAL timing to 8-14 degrees. See if that helps.

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Question 50

Timing Adjustments

admn · Accepted Answer

Q: Timing Adjustments

I am having a problem setting my timing on my car to the indicated specifications. What do I need to do to fix the knocking on my HO engine?

A: I've never had that much of a problem with the timing on my 400. But I don't pay that close attention to the timing at idle. For mechanical advance (with the vacuum advance hose to the distributer removed and plugged), I set the timing at 32 degrees BTDC at about 2600 RPM (you'll need some timing tape for this). Once you set the mechanical advance, disconnect the vacuum advance hose at the carburator end and hook up a vacuum gauge to the carb that you can put inside the car. Then go out for a little run and write down the maximum vacuum when running at a constant speed with the engine at 2500, 3000, 3500, and 4000 RPM (make sure the road is somewhat flat). Go back and hook up your timing light again, set the engine speed at about 2600 RPM, connect a vacuum pump to the vacuum advance and pump it up to the your max vacuum reading you read in the car. Your total advance should be 50 degrees at this point (that's what I set mine too, I know people that go higher, but not much). If you have a distributor with adjustable vacuum advance you can adjust it until you get 50 degrees. If your motor is spark knocking you'll have to back off on the timing until it doesn't. But that ussually means there is something else wrong, like your vacuum advance is advancing your timing too much, you're running too lean a fuel mixture at max advance, or you're running to high of a compression ratio for the fuel you're using. I think most people run to high compression for street gas. I don't think you should run more than 9.5:1 on plain old 93 octane. And most people with older cars have compression ratios over 10:1........................................spark knock city.................. If the production timing marks weren't cast right into the timing chain cover, I would have taken them off a long time ago. Timing tape is pretty cheap and alot more accurate. That's my 2 cents worth anyway.

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Question 51

Timing Adjustments (Revisited)

admn · Accepted Answer

Q: Timing Adjustments (Revisited)

A while ago there were a few of you who said that after they set their timing, that a timing light showed it to be WAY advanced, like 20-30 degrees. I think I asked once before but I'll try again. If you're not setting it with a timing light in the first place, what are you setting it with?

A: I originally asked this timing question. I set the timing by ear and feel. I loosen the distributor and advance it until the engine starts to miss, then back the timing off a little. Then I rev the engine and see to see if it pings. If it does ping, I retarding the timing a little rev the engine again. I keep doing this until the pinging is gone or very, very minimal.

All the mechanics I know never use a timing light and use this method.

A: The only problem I have ever had with using that method is that with the timing set to run it's best at 700 or 800 RPM, often it will have too much initial timing to start easily. What I try to do is set the initial by what will start easily (as much as it will take w/out trouble) then adjust the weights and springs to get the total advance I need, and have it start coming in fairly early, like 700 or 800 RPM. It's a lot of trial and error work, but it has always worked well for me. Then once I have it right I check it with a light and write it down so that I can put it back next time I have the distributor out.

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Question 52

Timing Chain Cover Replacement

admn · Accepted Answer

Q: Timing Chain Cover Replacement

I found the timing chain cover to be crack and a waterpump with bad bearings. My car is a early 1968 with a cast iron waterpump. I understand the timing chain covers and waterpump on 1969 and later are different. Does anyone know if these are interchangable?

A: 1968 and earlier engines used an 8 bolt water pump and matching timing cover. The 1969 and later use 2 flavors of an 11 bolt pump, and basically 1 flavor of 11 bolt timing cover, part number 482893 or 9796345.

So, to answer your question, you can convert to the later 11 bolt timing cover as long as you use an 11 bolt water pump, and the matching pulleys. You have to be careful to get the pulleys that match the water pump. There were 2 variants offered in 1969. Basically, get a 1970 or later pump, and get the pulleys and brackets for a 1970 and later V8 and you'll be OK. All Pontiac V8 timing covers will fit all Pontiac V8 engines.

Otherwise, look for a 1968 timing cover, part number 9790346. The 1967 V8 has a different part number, 978129, but I don't know how it differs. 1966 and earlier also have a different number. I believe they differ in the location or appearance of the timing marker. This could also be true with the unique 1967 and 1968 covers as well.

Some used parts vendors such as Frank's Pontiac Parts in Ramona, CA, Steve Hanson in northern CA, or even Firebird (Camaro) Specialties have clean used covers for sale. It may be easier to locate a 1968 cover than find a later cover, and get the right pulleys and brackets so that all of your belts line up correctly.

A: The timing chain cover averages 125.00 or more and mine was pitted also from age and you cant file them down because the pullys will no longer match up so I shopped around and found Jim Butler Pontiac has the best price. That was hard to beat. His web site it http://www.jbp-pontiac.com

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Question 53

V-8 Into a 6-Cylinder Compartment

admn · Accepted Answer

Q: V-8 Into a 6-Cylinder Compartment

I have a 400 block built and plan on putting it in the 1967 326. I was wondering what special bracketry I mich need to accomplish this.

A: If you use all of the bracketry from the 326 motor, you don't need anything extra. About the only possible hang up is if your block is a 75 or older. After 1970, all Pontiac V8s were cast with 5 holes on each side to allow installation in either early or late chassis. Some 75 and later engines either don't have all of the necesary holes tapped, or they aren't present at all. New motor mounts are usually a good thing since after 33 years, the originals are a bit tired. In general, 326, 389, 400, 428, and 455 all interchange.

Other than that, this should be a simple bolt in. Just don't try to interchange your 1967 accessories or brackets with any later stuff. You will risk pulley alignment problems.

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Question 54

Vacume Hose Diagram for 1968

admn · Accepted Answer

Q: Vacume Hose Diagram for 1968

I am in need of the vac hose diagram for my 1968 350 ho with the dual vac advance. No a/c or air pump. The advance has been replaced with a single port which is WRONG so I want to put it back right along with the plumbing. Thanks in advance.

A: I don't have a complete answer but maybe this will help.

There should be a themostatic control switch which mounts on the passenger side of the intake. It will have 5 ports on it. One (DA) goes to distributor advance. One (DR) goes to distributor retard. One (CA) goes to carb advance - I don't know which this is but I think (??) it is ported vacuum. One (CR) goes to carb retard - I don't know where this is. The last one goes to to manifold vacuum (at the bottom rear of the carb). If you have an Automatic, the vacuum modulator also goes to manifold vacuum.

Also, the AMES catalog sells both the control switch ($35) AND correct color vacuum hose kits ($54 - ouch). They also have a pretty good diagram of a 1968 4bbl in their catalog and I'm guessing they send directions with the kit.

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Question 55

Vacuum Hose Diagrams for 1968

admn · Accepted Answer

Q: Vacuum Hose Diagrams for 1968

Hello all! I am in the midst of rebuilding my 1968 firebird 400 conv. (little by little). I am working on the engine for now, while I am waiting for my Year One parts to arrive... I read the message a little earlier about overheating. Which unfortunately, my poor car is doing! It mentioned the vacuum advance hose being on 'manifold' rather than 'ported' vacuum. I was wondering if anyone might be able to point me in the right direction for a Diagram of CORRECT vacuum hose routing (or some dang good pictures), for a 1968 400. It seems the owner before me, decided to just cap off almost every vacuum port available... so this could be one cause of the overheating... ?

A: Pictures of the diagrams:

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Question 56

Valve Adjustment

admn · Accepted Answer

Q: Valve Adjustment

I am about ready to put my engine back together but I can not find any information how much to tighten the valves.

A: The valve adjustment on a STOCK Pontiac is straight forward.Tighten the lock nuts to 20 foot pounds and your are done.Pontiac made it nice and easy.Even with the aftermarket cam I had in my 1967 400 I used this spec and had no problem for the 10 years I drove the car after a rebuild.

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Question 57

Voltage Regulator Mounting on a 1967

admn · Accepted Answer

Q: Voltage Regulator Mounting on a 1967

Could somebody please look at their 1967 and tell me how the voltage regulator mounts? I took mine off of project bird over a year ago and am having troubles figuring exactly how it goes back on. The regulator has 3 mounting holes but I can't seem to get 3 holes on the rad. support that match up. There seem to be lots of holes in the vicinity and one hole has a rubber grommit in it.

A: The regulator mounts to the hole with the rubber grommet, plus two others that used to have grommets, way up near the top of the support. One of them is actually under the lip when viewed from the front of the car. Holes are about 1/2" diameter. BTW the rubber grommets have a built in threaded insert that the regulator screws go into, and compress them, sort of like a pop rivet does when you install one.

A: thanks for your response on the voltage regulator mounting. I found the three holes and even found new rubber bushings with nuts (called well nuts I found out) at Kragens Auto Parts.

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Engine - General Info (57)

350 Motor Mounts for 1969

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455 Swap

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670 Heads

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A/C Reserve Vacuum Tank

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Accessing the #2 Plug

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Adjusting Valves on a 350

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Backfiring Problem

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California AIR System

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Cam for a 1968 400

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Chevrolet Engine into a Firebird

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Dealer Service Information Bulletin 68-I-14 – Viscous Fan Clutch – Improper Diagnosis

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Dipstick Problem after Rebuild for 1967

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Distributor Vacuum Advance Valve Assy

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Dual Diaphragm Distributor

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Dual Port Advance for 1968

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Engine Rebuild

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Engine Rebuild (Revisited)

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Engine That Sat for 5 Years

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Filler Panels

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Firebird Throttle Cables 1968 / 1969

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Firewall Difference Between AC and Non AC for 1968

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Heads (061’s) for 1967

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Heads for 350 2-bbl Converted to 4-bbl

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Kick Down Switch

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Low Oil Light on New Engine

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Motor Mounts Left vs. Right

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New Engine Break-in