I'm helping a friend rebuild his 350.

They are center bolt heads with 64cc combustion chambers, my friend thinks they came off a suburban, the casting number is 10110810.

I wonder how these differ from the centerbolt heads used on the TPI f-bodies. I was under the impression that all the centerbolt heads were the same.

If your interested the rest of the combo will be:

- Edelbrock performer carb
- Holley contender intake
- Comp Cams 268 cam 224/230 @ .050
- 1 5/8" headers
- 9.5-10.0:1 compression

I'm hoping for 340-360 hp and 370-380 tq

 

thats the HP you want at the crank? I think it will be close.

Heads are the place to spend the money. Those heads will do o.k. but not optimal.....If you can get some extra money PapasmurfZ28 has a set of heads for sale that would work really good for you. If not try out what you have....

 

Any ideas on what the differences are between the heads? I'd like to get more compression running .015" gaskets instead of the .039" stock size. I've been worried about them being too thin, I'm wondering if anyone has used these with good results.

Honestly if it were my car I'd port a set of vortec's and run one cam size larger with 10:1, airgap, holley etc. I'd probably even attempt some janky homemade turbo setup (lower compression obv) but this is for a friend so I'm pinching him together as much hp as possible for as little dollar.

I'm probably going to be getting a wideband soon so I'll be able to dial in his carb too.

 

I would run the .039 gaskets. is the block decked? if it is you will need the thicker gasket to get some quench in it.

I would try to cut the heads down and get the cumbustion chamber smaller. I think the corvette used a 58 or 54 on the l98 heads

It will stil run pretty good

 

The Corvette used a 58cc combustion chamber.

I'd choose the head gasket thickness based on the current piston-to-deck hieght at top-dead-center. If the block hasn't been decked before, then the piston is probably sitting .025 to .035" in the bore at top dead center. If it is, then it would make sense to use the .015" thick metal head gasket to get your quench distance to be around .045 inches. If, on the other hand, you find that the piston comes up to the top of the deck, it would behoove you to use the thicker gasket.

In other words, choose the gasket that best sets the quench distance (distance of the piston to the bottom edge of the cylinder head) to around .045" - .055". That will give you your maximum compression ratio (with the current combination) with a decent resistance to detonation, plus keep your pistons a safe distance away from the head under high-RPM operation.

 

thanks guys, I'm trying to convince him to take off the junk he has on there now. They are 333882's.

Would it be worth it to pull them off for the centerbolt heads?

 

An 882 head? My gosh, those heads have huge combustion cham bers, like 76cc or so. Very thin castings, prone to cracking, with open chambers. Moderate air flow capacity, about as good as an L98 cylinder head. Your buddie's compression ratio will be down in the 8:1 range. Not a very good head for performance. It was a decent choice in the mid-1980's when SBC cylinder heads didn't have many choices, but compared to today's SBC head technology, they are worth keeping around only if you are going to build a cheap motor for your farm truck.

You need to make some measurements of the piston volume, the piston crown-to-deck distance, then calculate how much volume you need in the head gasket and combustion chamber to make a decent, streetable compression ratio. Once you've figured that out, you'll be able to shop for the cylinder head. You'll probably be in the 58 to 67 cc range. There's a dozen different head choices out there that you can find for $450 to $950 per pair that'll fit the bill.