[goat69SD]

I have a set of #15 heads that I pulled off of a 455 engine. Are these any good? I probably wont ever use them but was wondering if there worth keeping. Not sure what the engine was out of but it was no salvageable. So saved the crank and heads.

[RocktimusPryme]

Generally speaking I think the consensus is that there isn't a huge difference between D port heads. Its not like an SBC where some heads are dramatically better than others flow wise. So somebody will want them.

It just boils down to the combustion chamber, and valve size as to which you select. The later heads like 6x-4s are often favored because they have screw in studs.

[thepontiacman]

Those are big car Pontiac heads off 455/360hp. 500 ft lbs at 2800 from factory.

They are good torque heads and should be 87cc. Just need screw in studs if using for high perf.

I ran those for years and performed well in heavy street car.

someone out there would buy them if you don't use them.

[433lemans]

These are small valve heads. I have a set that I had ground for big valves, tapped for screw in studs. After enlarging, the ports really need blending to smooth out. As a side note, I wanted a multiple angle valve job done on them, gave him the specs but the machinist took it upon himself to grind in radius seats. Don't know if this type seat is any good but we were done after that move. Hope to install on a 428. Good pump gas compression.

[mysticmissle]

i have a ported set that have had large valves and screw in studs added at some point before i got them, i have them on a 40 0ver 455 it scoots pretty gd, no complaints
i also have a stock set of 15s too

[b-man]

Those are a good head because of the 87cc chambers. A great way to either lower the compression on a ‘67 -‘70 400 or 428 with the original 72cc heads or go the opposite direction by bumping up the compression on later low-compression 400s that originally used 98 to 105cc heads.

The press-in studs need to be converted to screw-in for any kind of healthy aftermarket cams and valve springs but can be left as is for milder cams and stock low-lift factory performance cams like the popular 068.

The 1.96/1.66 valves sizes as they are perform just fine on a moderately built street engine but it’s probably a wash cost-wise to simply just move up to bigger 2.11/1.77 valves because they’re probably much easier to find and cheaper than the smaller valves.

[Formulas]

ARP 290-7201 rocker studs 104.00 at summit not a show stopper 1/2" inch bottom threads

Ive always wondered if the chamber size is the same as #64 same year heads

I have a 440 that needs a set of heads always wanted a set of #64 for it #15 would be close i have #11s that i will probably utilize

[b-man]

I’m sure they’re functionally equivalent to the #64 heads in regards to chamber size and port shape.

That 87cc chamber is really the only reason to use them. However if I was spending the dough to rebuild a set of heads I’d opt for some 6X-4 350/W72 400 heads. With a light cut on the surface you can bring them down from 92-95ccs to 87cc. The port shape of the 6X heads are much improved over the #64 and #15 heads and they will respond to porting work better as well.

Don’t forget there are two bonuses when going to the 6X heads over the #15/#64 heads, screw-in rocker studs and 2.11 intake valves.

Leave the #64 heads for the 1970 455 HO restorers, they bring very good money for this reason only but not because they’re really a great performance head.

[Formulas]

Bart have you CC'ed #15 and #64s then or just guessing on being equivalent

[b-man]

Not really guessing but they’ve both been listed as 87cc. Of course most factory chamber volumes as listed end up being slightly smaller numbers than actual measurements. And no I’ve never personally cc’d any Pontiac heads.

Both the #15 and #64 heads were used on 10.25:1 1970 455 engines so there’s that.

[mysticmissle]

the set of 15s i cced at home, was 88-9cc and they had a clean up cut and the larger valves already in place.

[Formulas]

Listed ... yeah almost all 68-70 400 heads are listed at 72 CC and they are not, just looking for accurate information

Advertized Pontiac compressions were not true either so theres that,
again looking for accurate information thats all

Goat69SD they are worth keeping VRS scrap yard .. good for a 421-455

[SD455DJ]

#15 heads are pretty darn good stock. Here is dyno sheet of my 455 (+.040 = 464.4 ci) with stock untouched #15 heads with new 1-pc. Ferrea 1.96"/1.66" valves, new CC single springs w/dampers, and stock pressed-in rocker studs that we had pinned to prevent pull-out. The heads were cut minimally to ensure trueness and measured 90 cc's average with a true 9.95 static compression ratio. The cam is a Summit 2802 (224/236/114 @ .466"/.488" lift installed at 108), stock iron intake manifold, 750 Q-jet, and log exhaust manifolds with Pypes 2.5" mandrel downpipes. We had .040" quench with the pistons .010" below the deck and used .030" Cometic head gaskets. The 2802 is a bit too small for the combo.

It made 390 hp at 4600 rpm and 512 lb-ft torque at 3400 rpm. It would have made 400 hp/525 lb-ft with RA manifolds.

Dennis

[b-man]

Of course all the “listings” are fine to shop for heads in the cc range you’re looking for, the only truly accurate chamber measurements are the ones you do or your head builder does on your heads.

We’ve all seen 72cc “listed” heads measured anywhere between 66 and even up to 82ccs depending on the year and casting number.

Anyone else’s numbers are just that, their measurements.

I had one of last sets of hand ported 6X-4 heads Dave at SD did before going CNC. I moved them on before ever using them, they had the minimum milling done for cleanup and they ended up at 94ccs. You see these listed at 92ccs I’m pretty sure so again probably anywhere up to 96 or possibly 98 to start.

[goat69SD]

Thanks everyone for the information. I doubt I ever build another Pontiac engine. I will not scrap them for iron weight as I sometimes do because I generate more than I can store But at my age slowing a bit building cars. I have one more charger I want to do after the GTO (if I live long enough) But 67 and still building so I guess that's more than some. Not really into the whole selling thing. Been burnt bad before selling through mail , UPS etc.

[steve25]

Thanks for posting that info and dyno sheet Dennis!

You had nice BSFC numbers going on there also!

[b-man]

Originally Posted by goat69SD

Thanks everyone for the information. I doubt I ever build another Pontiac engine. I will not scrap them for iron weight as I sometimes do because I generate more than I can store But at my age slowing a bit building cars. I have one more charger I want to do after the GTO (if I live long enough) But 67 and still building so I guess that's more than some. Not really into the whole selling thing. Been burnt bad before selling through mail , UPS etc.

Selling heads locally is easy for the seller and cheap for the buyer, however depending on where you live you might never have a chance of making a local sale.

Shipping costs are crazy expensive, depending on the distance you’re looking at 2 to 3 hundred dollars for a pair, I know because I just shipped a pair from CA to FL and it cost $275 via FedEx ground. If you don’t know how to package them as the seller then good luck, the shipping will cost even more.

I don’t understand how you could get ripped off as the seller but I guess anything is possible. Keeping them around if you’re never going to use them is fine if you have a lot of storage space but giving them away to a Pontiac friend or selling them to the scrap man is better than letting your heirs deal with them.

[goat69SD]

As far as heirs there will be no issue. My wife and I have a lot of stuff we both collect memorabilia and I have a 65 x 40 shop that I keep around 6 or 7 old cars in. We decided rather than burden the kids we would have it in our will that there will be an auction on everything including the house and property. Funds to be split equally. I sold a very rare mopar intake manifold a few years ago. An off set dual 4 from a 426 street wedge engine. I had a pal-pal account. He paid to that. Then the PO didn't show the last place the package was at on the tracking. He said he didn't get it and pay-pal took 1350.00 out of my account. The PO wouldn't pay for it because they said they delivered it. But wouldn't represent this in court. As they said it wasn't there problem. We fought this for months and never got a thing. And I do trade things like this local rather than sell. But don't know any Pontiac people in this area. You don't see many around here. I am just saying I won't trash them for now in case I find someone who wants them. I hate seeing usable parts be destroyed when there getting harder to come by.
It's all good!
Thanks

[scott70]

1970 #15 heads are for the base 360 hp 455 with small valves and pressed in studs. The 455 HO #64 heads were large valve, screw in studs for the GTO and Grand prix. Both labeled as 87 ccs but most are in the 90-93 area. Pop in the 2.11 intake and thread for studs and youve got a decent set of heads.

[geeteeohguy]

Originally Posted by b-man

Those are a good head because of the 87cc chambers. A great way to either lower the compression on a ‘67 -‘70 400 or 428 with the original 72cc heads or go the opposite direction by bumping up the compression on later low-compression 400s that originally used 98 to 105cc heads.

The press-in studs need to be converted to screw-in for any kind of healthy aftermarket cams and valve springs but can be left as is for milder cams and stock low-lift factory performance cams like the popular 068.

The 1.96/1.66 valves sizes as they are perform just fine on a moderately built street engine but it’s probably a wash cost-wise to simply just move up to bigger 2.11/1.77 valves because they’re probably much easier to find and cheaper than the smaller valves.

THIS^^^^. About 15 years ago I picked up a set of #15's to use on my '67 GTO with the original engine. Engine was stock with a .030 rebuild, stock carb, dist, and an 068 cam. I had the screw in studs installed and new (small and expensive and hard to find) valves installed, etc. I ended up with about $1400 into the heads (back then) and in hindsight, should have bought new aluminum heads. That said, they have been trouble free, and with the TH400 and lazy 2.56 rear I installed in the car, they make for a nice solid combo that gets killer fuel mileage and runs well. Lots of low RPM torque and runs on 91 octane, which I could not do with my 670's or #12 heads on this engine.