Different heads

[67weimann]

I got a good one for all the gear heads here. I pulled my valve covers today to clean 'em up and why I was in there, I figured I would see what heads I actually have. So I noticed they were different. Wow...who would of thought
Per Mor Tec here's what I have;
3890462....66-67...302/327/350..Camel hump,no accessory holes,64cc chamber
3782461....64-66...327......Camel hump,no accessory holes,160/62cc port volumes,62cc chamber
How serious is this?

[Moneypitt]

Alot of those chevy heads are interchangable for most automotive applications, grocery getters, work trucks, the family sedan....Unless you are trying to wring every ounce of HP out of an engine you probably wouldn't notice any difference. Yes, matching heads, with equal eveything is better, but as long as the castings are simular, and the valves are the same size, those 2 CCs of chamber difference won't matter. IF you ARE trying to squeeze every bit of HP out of it, replace them both with some of the later model stuff, aftermarket angle plug 2.02s...........MP

[fc-pilot]

I am going to agree with Ray on that one. As long as you are not trying to run tight compression, or need every bit of performance it won't hurt you. Many of the factory motors had machine work that would have produce variations bigger than that, so I am not too worried. On top of that is the question of how precise the original casting may have been, so with these possible variations I would not worry too much.
Now if you plan on doing a performance rebuild it might be better to get a performance set of aftermarket heads. The performance increase is great and the price keeps coming down.
Paul