I have a 326 Firebird with a 4bbl Edelbrock performer 600cfm carb and performer intake and Black Jack hedders. I want to put my 326 aside and build a low budget 350.

My finances are low so I can't afford to build a 400 or 455
I met this great guy a few months ago that has a lot of Pontiac engine parts. He has just purchased a 455 for his 69 Firebird and is offering me the 350 that is in his car for a good price as a running motor less the heads. It is not the original 350 for the car and all I can say he is running low 15's with an th350 and a posi rear (not sure what gears he running)

Now for my question he has 3 sets of heads i can choose from These are #11 1970 D-ports from a 350 cu in with 1.96/ 1.66 valves @ 73 cc. And I have a set of # 7H1 heads. These are 1972 D-ports from a 350 cu in with 1.96/ 1.66 valves @ 80 cc and the last set is from the 455 motor he has just bought they are 6x heads that have been skimmed a little just to true them up and have 2.11/1.66 valves and roller rockers.

I get my heads info from here.

http://wallaceracing.com/head1.htm

i have a copy of Jim Hand how to build max performance Pontiac V8's and it says the difference between a motor with 8:1 and 10:1 compression is worth 6% in total power.

which heads would be best or would I be better off putting my 326's 140 heads which are 9.2:1 cr on the 350 motor because I think all these heads will be a lower cr.

He is also offering me a Pontiac N cam which according to my Jim Hand book is 273/282 advertised duration 197/206 @.50 duration 111.5 lobe separation and 107 intake centerline

I have a B&M holeshot 2000 high stall converter ready to go in and that is left to get the car to hook is a posi rear and some better gears as I have 2.56 open gears.

Your choice will have to take into account available fuel.

I think the 6X and 7H1 will have chambers too large to deliver reasonable performance on a 350. The #11 may be adequate for a cruiser, but not with that cam.

If you have access to good quality high octane fuel without ethanol, you can run the 140s, which calc out to approximately 9.8:1 on a 350, as long as you match up all the valvetrain components.

The cam is a lot of cam for a 350, you may want to consider a slightly more moderate cam for street drivability.

Thanks for the reply, good quality high octane fuel is available such as Shell optimax and octane booster is also available. I only do 500 miles a year and want to drive the car to say 3 or 4 drag meets a year and just have some fun. I will be on the look out for some better heads but Pontiac heads are a bit thinner on the ground in the UK than the USA

I was thinking the 6x would would lower the CR too much and I was thinking have the #11 heads. I have a B&M Holeshot 2000 high stall TC to go in and I am on the lookout for a posi rear end and some better gears as I have 2.56 open diff

I don't really want to make a cruiser!
Do you think the Pontiac N cam would be out of the question then? Because while this motor is out I want to put a decent cam in there. I have the finances for a new cam. The 350 has a healthy oil pressure and just needs a new rear main seal. Any recommendations for a cam.

Cheers Andy

A better cam for a moderate/street 350 will have about 205 intake and 215 exhaust duration with about .450" lift and a lobe separation angle should be 110-112 degrees. That will allow the 350 to produce more torque across the board and noticably more power in the upper range while still being very civilized.

Make sure you degree it correctly; 3 degrees advanced seems to work well.

Think i still a have new Pontiac grind(enhanced by Crane) around 214-218 dur on a 112-114 lsa range.
I'll look tonight.

It would be cheaper to build a 400 than a 350. Do the math with parts and you will see.

I would stick to the #11's and leave it as a running motor.

Vikki,

I have 18 heads. Apparently they are high compression heads and should require higher octane gas. I put premium or regular in it 10 yrs ago with no real noticeable difference. What would the symptoms be for this? It was always somewhat coppy but I assumed that was the fireball cam. I am going to rebuild it again.

Have a listen: Nanananan naaaa

My car is a 400 with 1970 #11 heads and runs pretty good. Thinking of an upgrade to better heads. You do know you have to drill and tap threads for headers? #11 heads don't have the outer bolt holes drilled on the exhaust. Definitley go 400 build I had less than $1200 in my build. That was having crank turned,freeze outplugs,cam bearings installed. It didn't need bored so just a good hone job. Heads were bought from the machine shop for $225

Gus, has your engine been rebuilt? If so, what pistons were installed?

Rebuilt it in '81. The engine was built with parts from another 68 motor where the block cracked (no anti-freeze). The pistons are aluminum Jahn's pistons (size unknown).

see http://picasaweb.google.ca/105908860112140983297/350HO#

Thanks for the replies guys what you have to remember is I am in the UK so it,s not cheaper to build a 400 here. Engine work is expensive here and I have to pay import duty 4%, shipping and vat at 17.5% on any parts I buy from the USA most of the people over here who sell American car parts here are rip off merchants and charge far more than they should for American car parts. it's normally cheaper to import stuff yourself!

The 350 I am being offered is a running motor with a good oil pressure and just needs a rear main seal. I will of coarse check the main bearings and con rods bearings to see what condition they are in while the sump is off. But I hope to just add a decent cam and either put the 11 heads or the heads from my 326 which are 140 heads on there put in my B&M Holeshot 2,000 stall and then try and source a posi rear with some better gears.

I don't have the finances for a full rebuild at the moment this is going to be my winter project I should get the 350 in the next month or so so I will have more info on it then.

I think the 11 heads are your best bet. I have 11's on a 350 and it runs great. If you are going to do all this in the next month or so like you say you should set it up for the way the car is now with the 2.56 gear and what sounds like a mild converter. You will not be happy with a tight converter and a hot cam with 2.56's, no way. It will be a dog.
If you have any money spend it on those heads. A good valve job, keep the 30 degree intake seat. Have them slightly milled to make sure they are true, reduce your quench distance, and give your compression a slight bump. Actually, have them zero decked if you can get the help to calculate how far in the hole your pistons are.
With that 2.56 gear in the car I might go with 1.65 rockers and new springs and keep the factory cam.

Thanks for these 2 good replies, I have to take out the 326 to put the 350 in and while it's out I will swap the TC's My next priorty is to change the complete axle as soon I can find a posi at the right price. This will be much cheaper than buying a posi carrier and gears for my 8.2 axle. I am looking to go 3.42- 3.73's

Now I have the 4bbl carb intake and hedders it lights up one rear wheel so with more power I will have more trouble getting off the line.

FirebirdMike that is good info on the N cam, do you know what cam my 326 2 bbl auto with 140 heads 250hp has in it from the factory
Cheers Andy

Right here is the latest I picked up my #11 heads last week as I met my mate at a drag strip meet at Santa Pod. He also brought the Pontiac N cam which was wrap in cloth and taped up. Anyway when I unwrapped it had a badly worn lobe and is scrap. My buddy apologised as he didn't unwrap it as he wasn't going to use and gave me some money off the deal to make up for it.

So I set to work on decoking the heads and all the guides are fine except one which has loads of wear and needs a new valve guide pressing in so I got a quote and I may have this done or not because brilliant guy as my mate is he gives me another set of #62 heads aswell. These have bigger valves 2.11 and 1.77

One slight problem is he needed the screw in rocker studs to go on his 6X4 heads he is putting on his 469 motor.
I looked at the #11 heads and they don't appear to have screw in rocker arm studs unless are they under the push rod guide plates? Because I haven't removed those yet!

Anyway I must decide which heads to use or I could try one set and later try the others.

The 350 short motor I got is from a 1970 Firebird and has the block casting number 9799916. I was told is was a manual transmission car so does this mean it would have had a better cam than the auto?

I have to decide what cam to put in there as I don't want to go too wild. I am going to run this motor as it is because the bores look good my mate wasn't having any problem with the motor and it has a healthy oil pressure. All I need to do is the front and rear main seals.

I also have a good timing chain to put in there as my mate says there is a bit of slack in the 350's timing chain and he has 5 timing chains sitting on his self.

He doesn't just give me a stock one he gives me a hi performance timing chain which I have forgotten the name of already! What a fantastic guy!

He was running the 62 heads on the 350 69 Firebird with a TH350 and a Saturday night TC and a posi but he's not sure what rear ends gears he has. He was running low 15 1/4 miles not sure what speed.

So I have to decide which heads to use #11 or #62 and I am thinking the #62 heads and then what cam to go for. I would like to use the stock springs on the 62 heads as they look pretty new! I will be driving the car to the track and only drag racing 3 or 4 times a year at for fun and I only did 400 mile last year so it's not a daily driver. I have a 2000 stall B&M holeshot TC to go in and I will have to do something about my open 2.56 geared diff.

I have finished decoking the heads and I then started to strip some stuff on the short motor. I removed the fuel pump and then the bottom pulley and the harmonic balancer or damper. I then removed the timing cover and there was loads of slack in the timing chain as my mate suppected. I have the new comp cams roller chain to go in there so I had a quick trial fit of them as all the timing marked are lined up.

I then took out all the lifters and labeled them so I know where they go back if I need to. Then I removed the cam which is in good condition all lobes are good. I noticed it has an H stamped on the end so I stopped my work there as I have to decide what cam to put in there.

So I look up in my Jim Hand performance Pontiac engine book and a H cam looks a pretty good cam advertised duration 302/320 duration @ .050 224/236 and 115.5 lobe separation intake centerline 113 And further on I read it is know as the Ram Air III cam as far as I can see the lift is only 0.407"

Now I am wondering if I should just go with this Ram Air III cam or is it worth go for the higher lift of the above cams?

what do you think I was thinking of the comp cam 260H or the 268H or 275DEH

I looked at the spec of Pontiac valve springs and the spec of comp cams 988-16 springs and found they were almost identical can I use my stock valve springs with these cams

PONTIAC VALVE SPRING KIT replacement for stock springs

Falcon Classic prides itself in offering quality engine parts for vintage American muscle! This listing is for a FULL set of thirty-two (32) valve springs (16-inner; 16-outer) for the following Pontiac V-8 engines:

* 1965-67 326ci
* 1967-77 350ci
* 1965-66 389ci
* 1967-79 400ci w/ AUTO Transmission; except Ram Air
* 1965-66 421ci
* 1967-69 428ci
* 1970-76 455ci; except Super Duty

P/N VS9017-16+VL355-16. We'll even include hardened locks for FREE! Valve spring specs are as follows:

* OUTSIDE DIAMETER: 1.390"
* OUTER SPRING ID: 1.050"
* INNER SPRING ID: .768"
* SEAT LOAD: 93-LBS. @ 1.600"
* OPEN LOAD: 243-LBS. @ 1.130"
* COIL BIND: 1.000"

comp cams 988-16 springs

O.D. of Outer Dia. 1.384
I.D of Outer 1.060
Dia. 2 I.D. of Inner 0.804
Dia. 3 Damper N
Seat Load 117@1.600
Open Load 232@1.100
Coil Bind Rate (Lbs./In.) 1.000
rating in lbs 230lbs
Titanium retainers 730
steel retainers 1730,740, 743,744

A RA III is alot of cam for a 350 with 2.56's and an auto. If I recall correctly pontiac used those in stick cars with larger displacement and probably higher compression. You can run what you brung and it will run but from what I have read so far about what you want, I'd look at a smaller cam. It's just going to be lazy with the 2.56 gear until it's rev'ed up. I think cruising will just be more fun with more throttle response at your cars typical rpm with a better matched cam.

Here's an update on where I'm at now I managed to do a swap with my 2000 B&M Holeshot TC for a 3000 B&M Holeshot so as money is tight I decided to stick with the H cam for now.

I went ahead last week with the motor swap took the 326 out as a complete unit and set it aside. I left the TH350 in and swapped the TC supported the TH350 on a jack and dropped the 350 short block in lined up the dowels. I left the headers out because I was waiting for my header wrap to come from the USA. I also left the motor mount bolts out as I wanted to lift the motor a inch or so to put the headers back in from under the car.

I marked the Dizzy before I removed it from the 326 with it set on No 1 at TDC and I scribed a line down the dizzy and onto the block noting where the vacuum canistor was pointing and I labelled all the spark plug wires. I transfered this marked to the 350 block and put the dizzy back in so I was close to a running postion for timing.

I put the heads on torqued them down, set the rockers for zero valve lash plus 1/4 turn. put the rad back in and then bolted up the power steering and alternator! This is whan I hit a snag as none of the pulleys lined up! The 350 water pump is longer than a 326 and my buddy did not give me the water pump pulley so I was using the 326 one. Anyway after a quick check on here I found out I had to swap the timing cover and use all the 326 pulleys harmonic balancer and alternator bracket so everything lined up.

I got my header wrap to cut down under hood temps and wrapped them before putting them back in. I had to order nuts and bolts to fix the TC to the flexiplate as there was no captive nut on the 3000 TC.

Once the intake was back on and all the hoses and cables back on I filled the oil and water/antifreeze. I was then ready for start up but the starter would not engage so I shimmed it until it did.

The motor fired up second turn of the key, it took a while for the lifters to stop clattering but once they had it sounded fine oil pressure was 60 psi cold and about 45-50 hot water temp was fine about 180 ish. I topped up the tranny fluid and went for a short drive round the block.

I set the timing which was about 14 BTC to 10 BTC and she's running fine. After I went to my American car meet I tried a little start line action not giving it full throttle but enough for all hell to break loose! This baby gets up and goes now it feels like I gained a hundred Hp over the 326!

In reality it probably only about 50 HP but man does it feel like a different car it spins the wheels about half throttle form a take off. Now I need to get a posi axle for sure as all the wheel spin is on the passenger side only. It gets away well as long as you feed the power in gently.

I have the Hot Rod Drags car meet at my local drag strip in a few weeks so no time to sort the axle before then so I will give it a try as is for now. I not expecting quick times my mate was running low 15's with a very slack timing chain in there and a posi axle so now it has a new crane cams roller timing chain if I can get low 15's I will be happy for now

I only have one question what should the timing be for a 1971 350 Firebird motor with a H cam and a vacuum advance dizzzy.

Unplug the vacuum canister and set the total advance to about 35 BTDC. To do that, rev the engine up gradually until the timing stops changing then set it to 35. Let the engine drop back to an idle and note the initial timing. That will likely be around 12-15 degrees depending on how the distributor is set up.

Usually the mechanical advance should be all in by around 3000 rpm but that varies slightly depending on engine combo and fuel quality.

As you've found out, the H cam works quite well even in the "little" 350 as long as you have enough stall speed!

I set the timing at 12BTC and set off for my drag racing weekend. I went to the Hotrod drags in the UK this weekend and the car drove well on the trip there so I decided to run the car on the track a couple of times just to shake it down.

I met my mate Gary there who sold me the 350 motor and he told me the first time he drag raced that 350 motor he span a wheel the full length of the track! I though Gary was pulling my leg!

So I decided for the first run I would drive around the water box and not do a burnout. The Lights changed and I did not give full throttle as it was a shake down run. A huge screech and the passenger wheel started spinning so I backed out of a a bit to try and stop the spinning wheel. This went on until about half track before it finally gripped, if I had left my foot in there I could have spun a wheel the whole length of the 1/4 mile!

So I get the timing slip thinking maybe a 17 second run! No 18 seconds dead at 80mph! I thought that's slow, So next time around I thought I am going to do a burnout even though I will only be burning out one tire! I thought this isn't going to make much difference!

So I do a short burnout pull to the line and the car hooks right up no screech no spin just launches! I keep my foot in it and let the auto box change gear in D and cross the line. the run felt good but I have no Idea what the times gonna be.

I get the timing ticket and 15.6 at 86mph! I am over the moon with that for a non posi car. I meet up with Gary and I know he was running 15.3 with a posi and Santa Pod and he says the best he ever got from that motor was a 15 dead in his 69 Firebird Convetible with a posi.

So if I get a posi sorted out and some better gears say 3.55's as I still have 2.56's in there and open up the headers I think I could be knocking on the door of the a 13 second run which will be great!

That's great! Congratulations!

Not bad.
Any details on engine?
Heads, cam, etc.

The 350 motor is from a 1971 Firebird manual transmission. (they usually have a better cam than an auto)

Cam is a Pontiac H cam known as a Ram Air III cam
I don't know if this cam was stock in this motor but that is what was in there.

Heads are number 62 2.11/1.77 valves 72cc stock springs CR is at least 9.5to 1 could even be higher. It runs fine on UK pump gas which is 95 octane although I did put 97 octane gas is last weekend to go to the track.
I just stripped and cleaned them lapped the valves in added oil seals o rings etc

I have a new Crane roller timing chain
I think the motor must be putting out at least 300hp my mate Gary who I bought the motor off thinks it's nearer 325hp

I must get a posi axle sorted next so I can put power down through both rear wheels.
I also need a shifter because it's shifting in D at 4500rpm.

I think open headers will be worth 20 to 30hp the last car I raced with open headers then put a headman mufflers on lost .3 of a second my brother's car who I was racing at the time also lost 1/2 seconds with the exhausts back on!

Anyway next year when I have a posi I will have do a few runs with exhausts on and open headers my prediction is faster on open headers and a what a V8 should sound like!

I may have gained a few tenths loading the TC but then again I may have just got loads more wheel spin. Until I get a posi axle sorted it will be a lottery leaving the line. I want to be able to give it full power and be able to load the 30000 TC to the max until I pushing the brakes.

With the right gears I think I may get it into the 13's but that will have to wait until next year!

I do need to tune the carb as I am running rich now strange as this carb and intake were just right on the 326!

My mate who was running his 440 Dodge charger ran a full second quicker when he opened his headers and the track prep was better!

The two cars I was refering to when I raced my Brother were both SBC 350's and I had a short system with one muffler exiting in front of the back wheel for ease of removal at the track. Neither me or any of my mates have had a car go slower uncorking the headers. Once we are sure we have maxed the car out it always releases more power you don't have to have a restrictive exhaust!

As for the 440 track prep would account for 1/2 second the rest of the power would have come from uncorking the headers!

Let leave it there as your flogging a dead horse!