Hello all. My first question

My engine is ready to go to the machine shop to get a sleeve fitted in one of my cylinders - the other 7 are fine, but this one has a nice gouge in it. Whilst it is there it is a good time to get some other work done.

I am confused about what needs to be done to convert my '67 326 V8 to run on unleaded fuel. The plan is to use the car as often as possible, but not race, so I'm thinking it is worth doing; economically (avoid continual use of additive) and otherwise.

I've been reading around, including searching this site for some answers, but I am no more clearer about what I need done...

I have read the following is needed (one or a combination of...)

• hardened valve seats
• non-magnetic valves
• unleaded valve guides
• probably something I've forgotten
• or nothing, it'll be fine as is...

My machine shop said it could be fine to just use additive, depends how much use it will get. To convert, they suggest all is needed is hardened valve seats installed, but they say intake and exhaust both need to be done as there is so little space between the two. They did say the old valve will be fine. This contrasted what I've read in a number of places about non-magnetic valves (also, another machine shop suggested these) and replacing the valve guides.

Would it be possible for someone to clarify what work I need to get done in order to convert my old engine to run on unleaded fuel?

Thanks so much for your help. I really appreciate it.

Your old engine will run on unleaded fuel as is. With heavy use or continued use, you will see some valve recession (seat wears until valve sinks into head). When that happens, valve lift and performance will decrease.

Hardened seats are the normal solution. Valve guides are replaced due to normal wear. Stainless valves are an upgrade. My builder does all three, but he says that only the exhaust seats need to be replaced if the intake seats and valves have no damage.

Do you have a grade of fuel with sufficient octane for your engine? Is it a 326 HO, or a 326 2bbl?

Thanks Vikki.

The engine is a 326 2bbl. The Owners manual says Regular grade and also that the compression ratio should be 9.2:1. When I tested I was getting around 11.5:1, this may change with the rebuild though?

Anyways, Regular Unleaded over here is 95, Premium is 98 and 4 Star Leaded (few and far between, but available) is also 98. Which of the Unleaded would match up with 1960's US Regular?

Valve guides are not showing excessive wear so they'll likely be staying then. The valves should be replaced - the pair for the cylinder with a gouge are looking a little rusty and pitted. However, I was thinking about a rebuild kit from Kanter but they haven't replied as to what their valves are made from, so I'll start looking elsewhere. Does anyone have any advice on manufacturers of rebuild kits? Or should I start a new thread?

Thanks again.

What method is used to calculate your octane ratings? In the first gen era, fuel here was rated in Research octane and 100 was premium, 94 was regular. So you will be fine, as long as your compression is not really 11.5:1! How did you calculate that?

Ok, I got mixed up... my average compression was about 11.5 bar... not the ratio. Oops. I don't actually know what my ratio is. I got worried for no reason!

Octane ratings I think are still the Research Octane Numbers over here. So Regular will do, that's good.

Thanks again.

And since my gauges are not in bar, I think that's 169 psi, right? You should be fine.

You only need to replace the exhaust valve seats with hardened seats. Use whatever kind of valves Kanter supplies.

You are running a 326, the seat pressures will allow you to run without seats or additive.

If you were running a 326 HO or 350 HO with a high gear and mainly 3-3500 rpm freeway driving, I would say maybe.

I have torn down many a set of Pontiac heads at the shop and maybe 5 out of a 100 pair had noticable seat recession.

Installed seat pressures of 175 (closed) and 400 plus (open) to see accelerated recession on most Pontiac heads. If it has not happened by now (40 years) likely it will not. You see accelerated seat recession with roller cams and lifts of .600 plus.

My opinion? Save your money..If the heads need a rebuild, have them installed. If not, leave them alone. I would use Ferrea 5000 series valves, Comp Cams springs, locks and retainers.

SERDI cut seats.

I can get you the installed height and seat pressures if you need.

Thanks for the help so far everyone.

I have no experience with engines before now, but am thinking the heads need work and a rebuild, they're not looking particularly pretty, I know the light rusting and carbon buildup can be cleaned, but even so. I've put some pictures below, I don't know whether you could deduce anything from them...

The "bad" cylinder... obviously water has leaked in. These valves correspond to the cylinder with a gouge (which when doing the compression test was a good 5 bar/70 psi lower than the others)



This is representative of the other 7 "good" cylinders:


"Bad" intake valve:



"Bad" exhaust valve:



Representative of the "good" valves:



Also, in this one head (with the bad cylinder, coincidentally or not) all the valve guides have a notch in them, they don't look clean enough to be factory machined. The other head (all the cylinders are good) does not have these notches.


**If there are too many images, let me know and I'll make a page on my website and link to it. **

If any advice can be given on the state of my engine, and the necessity of a rebuild, it'd be greatly appreciated.

Those valve guides look like they've been knurled. That leads to less efficient oil control.

Replacing the valve guides and seals is good maintenance. What does that casting date say? What is the part number cast into the heads?

Those heads were already rebuilt. Those heads are K114 November 11th 64.

Do not reuse those valves. If you are going to rebuild them, heads are the most important factor in performance.

A good set of new valves, new springs..retainers and locks.

The difference in price between reusing old/new is maybe $250-325. You will pay $5-8 a valve for cleaning and resurfacing. A new quality valve is $10-15.

New springs are a great idea if you plan on keeping the car. You got the heads off...I would spend good, quality money there.

I would also install new guides..I would never knurl them. cheap fix when tolerances are loose.

Codes on one of the blocks:
K114
9780562

On the other block:
BO87
140

The guides are definitely knurled, clearer picture here - this is from the other head without the notches to the side of the guides:



So new valves, and new guides are recommended... it would seem silly not to do the valve seats then.

Does anyone have an opinion on the Kanter kits? Overpriced, good quality, etc? They seem to be a 'Marmite' company. Their complete kit for $1499 (fair bit more than I wanted to spend) contains the following:

• Pistons
• Piston ring set
• Main bearing set
• Rod bearings
• Connecting rods
• Cam bearing set
• Gasket set
• Timing chain
• Cam gear
• Crank gear
• Cam shaft
• Push rod
• Rocker arm kit
• Valve lifter
• Intake valve
• Exhaust valve
• Valve guide
• Valve spring
• Prelube
• Freeze Plugs
• Oil pump

I haven't determined whether the pistons need replacing, but as one of them has seemingly shot into the side of a cylinder, I would assume so. Also, my cam shaft has some chips but only on the edges of the lead up to the peak. The center width of the cams are pit-free. So the cam may or may not need replacing. Everything else in that kit I think I'll need. Although there seem to be no valve retainers or locks, only the springs.

... would I be better off ordering individual components?

Thanks again, you guys are great

I would go with a kit from Summit or Jegs and get the valves, guides, springs, cam and lifters elsewhere..maybe from your engine builder.

Give me a few days to check a wholesaler to see if I can get 326 rebuild kit.

That price from Kanter is high...I got their catalog maybe 10 years ago, seen the prices, and threw it away.

If you replace or recut the valves, the valve seats would need to be done...called a valve job.

If you rebuild the motor, I HIGHLY recommend a complete and thorough replacement of all components.

That way, you have piece of mind, and possibly can get some sort of "warranty/guarantee" if something goes wrong.

Just my .02

That 9780562 code is a 65 casting and I can not find it in my book...maybe someone else can locate. You do have a 67 head and a 65 head.

the 9780562 is an 8.6:1 326 2 bbl. The 140 is a 9.2:1 326 2bbl head. They are unbalanced. I highly recommend a set of matched heads.

Or mill off about ten thousandths off the 9780562 if the chamber is the same bathtub profile as the 140 head.

If it wasn't already done. That's all it would take? That's not much at all.

How were the compression readings left vs right?

Well that's interesting. As in annoying...

It's possible it's already been done though.
1357 bank (the '65 head):

• 7.6 bar . (110 psi)
• 11.8 bar (171 psi)
• 12.0 bar (174 psi)
• 12.2 bar (177 psi)

2468 bank (the '67 head):

• 12.3 bar (178 psi)
• 11.8 bar (171 psi)
• 12.1 bar (175 psi)
• 11.4 bar (165 psi)

They're close-ish.

I've just found the SD Performance website, I've emailed for more details, but it looks like you get the following:

• 2 matching head blocks
• all new intake seats
• all new exhaust seats
• ferrea valves
• springs, retainers and locks
• bronze guides
  
  for ~$1350

Seeing as I have been quoted £30-40 per valve seat and 16 need to be done (intake and exhaust too close together to do just the exhaust apparently) that's more than £500 just for new seats... without even buying new guides, valves etc... and this way the two heads are matched and "original". It's tempting so long as that $1350 is for a pair and not singles... Sound good?

Also, side note, my intake manifold has the casting number 9782894. Which appears to be a '66. My exhaust manifold is 9777755, which could be a '67 or '68? Boy is my engine a frankenstein !?

Those heads are probably good, but are priced a few hundred higher than I'd expect to pay my builder. But you are getting a "name"...do they also warranty them?

Your local shop's charge for valve seats is very high.

With those numbers, yes, the machining was likely done. It's probable that all those changes to your engine were done at a very early date, when the even older parts were readily available. Matching gaskets may get interesting, otherwise I can't forsee any major reassembly issues.

I can't do the USD to Sterling currency conversion, but here is an idea.

Maybe they are charging you to regrind the old valves and seats and install new hardened valve seats in the heads for the 30-40# price you were quoted. As I suggested, I do not believe you need seats at all, and if so, ONLY exhaust. I would like to see close up shots of the seats AFTER the heads have been cleaned up professionally. In order to install new seats, the heads have to be cut first to accept the new seats, then recut to accept the valve profile. That is ALOT of labor and cost that can be avoided by an honest machinist.

As I stated, a SERDI cut (valve job) for the heads is roughly $175-$250 USD and the valves $5-10 USD each. For a total of $80-160 for cutting and cleaning old valves.

You do not need anything for the new valves (cut/grind) so the price you were quoted (40-50#) should be much lower. A SERDI valve job for the heads alone is all you will need with new valves.

You do not need, from looking at the pictures, new valve seats..which is a huge cost for both intake and exhaust. You only need the old valve seats in the heads recut. We only installed hardened intake and exhaust seats if the customer wanted larger valves OR the seat recession was clearly obvious. I have seen a handful of Pontaic heads that needed both intake AND exhaust hardened seats out of maybe 400 pairs. By a handful I mean maybe 5 to 10. I think your shop wants to get money from you that you do not need to spend.

Here is a breakdown in what my shop charges in US dollars.

Disassemble heads, bake, shotblast, magnaflux $100
SERDI valve job $225
Comp Cams springs, retainers and locks $175-225
New guides $10 each, Machine for giudes another $5
Valves $125-200 (depending on quality)
Set up spring height and assemble $125-175

Includes valve stem seals.

You should be able, from looking at those pictures, be able to have those heads perfect for around $750-900 USD.

Those heads, to address the rust and condition...After a bake and shotblast, will look like new.

The 9777755 is a 68 Firebird left manifold...Be just fine with a 326.