I have a 1971 455. I was wondering what if any heads I could take from older Buicks, 430-425, for more fun. Or am I just way off, and not understanding some thing. graemlins/shield.gif

It is not the heads that changed the compression. The later oistons had a deeper dish. The 425 heads were for a completely different engine. The 430 and 455 were the same, but used some different parts. (intake and rocker arms)

You could always get your heads converted to stage 1 spec. This involves a little porting, valve seats recut, and nice big valves.
Malc

So could I take a set of heads from a 69 Wildcat? Then could I have them rebuilt, and made a little more woo?

You should check the casting numbers on the heads you have against the hi-flow heads in the buicks.net shop first. A '71 motor has a good chance of haveing good stuff on it already.

It is not the heads that changed the compression.

absolutely not true. the 71 and later pistons have a deeper dish, that's true, but the head volumes were also enlarged in 71 and again in 75.

the 70 455 heads and the 67-69 430 heads are all 69cc (not counting Stage 1 engines). 71-74 are 71cc (makes it easy to remember) and 75-76 are 78cc.

http://mywebpages.comcast.net/jholthenrichs/weightsn.htm << head volumes