Hey guys. I need a little help in deciding what heads I should be using for my BBC. The motor is a 496 with flat top SRP forged pistons. I right now have a set of peanut port 1986 454 truck heads that I don't plan on using. I was thinking about buying the edelbrock performer RPM oval port heads but I really don't want to spend that kind of money if I don't have to. I was doing some research on BBC heads and have seen that the 781 GM heads have the same intake and exhaust valves sizes as the Edelbrock heads. I believe that the combustion chamber sizes on the 2 sets of heads are also about the same. Am I right? I need to use the Oval port heads because I have a Edelbrock pro flo Oval port fuel injection system for this motor. I also plan on using a 100-150 HP shot of NOS as well. This is for a street car. My main qustion is I guess, Should I spend the $1800 or so for a set of the Edelbrock heads or should I get a set of the 781's? Is there really going to be much of a performance difference? I understand the benifits of having the aluminum heads but I just don't know if it's worth going that route. Also, if the 781's would be sufficient, does anyone have any that are any good that they would be willing to part with? Thanks, Jason

The Edelbrock's have 11/32nd valve stems with stainless valves that are bigger than the stock '781 heads; but other wise the ports volume and location are basically the same. The Edelbrock's also have a much thicker deck which will be important with giggle gas in the 150 horse range.

If it is strictly a cost thing, the Chinese are making copies of all of the heads that are made by other companies in their fair land were no one gets the privilege of an honest wage, environmental or safety concerns or copyright protection. :angry:

Of course I would rather cut off my arm than support them but it is an option.


Larger Dave

Pretty sure that 781 or any other oval head didn't come w/2.18 and 1.88's from the factory. I do know that the rectangulars (or some of them at least) did.

Problem w/factory stuff is that by the time you buy cores, have new guides, hard seats, valves, cut and blend for larger valves, springs, retainers, seals, etc, etc, etc, you won't be too far from a new set of aluminum heads.
And, your rebuilt iron heads won't flow close to the alumiun. AND, your car will be 75lbs lighter in the front. AND,the 11/32 valves are lighter, which should help revability. AND, whose to say your iron heads won't develop a crack and render them usless?
That motor your building wants goods heads...I dont think it pays to go w/rebuilt factory heads.

AND - I'm done :`)

Imho, get the 100 cc chamber heads for a flat-top pistoned 496 and if you can find something like a .028" composite headgasket that's aluminum head compatible, you will end up around 9.6 to 1 CR.-wise so you can run a decently sized cam to make GOOD power.

Mine with just 2.19"/1.88" valved cast-iron Merlin large oval heads and about 9.8 to 1 CR. custom ROSS pistons with .020" shims and the good old CC 282S solid cam, per D2k should make like 550 hp or so..

pdq67