The chamber spec on those heads is 67cc, not 64cc. You have to cc the heads to see what they really are.
Not a lot of replacement pistons available for the 307. The ones that are available have a modified lower pin height which drops the engine compression ratio. "rebuilder piston"
A bad thing for a naturally aspirated performance engine. (you want around 10:1cr),,, A good thing if you want to build a supercharged 307.
(You want a low engine compression ratio for supercharging 8.5:1 or less)
You can get this easily with what you got there.
Are you interested in that?
(camshaft: its a real bad idea to re-use a flat tappet cam when rebuilding a engine.)
get a new cam and new lifters.
Question? Does this 307 really need new pistons? (cylinder bore wear)?
How much power do you want? Whats the budget?
Last edited by F-BIRD'88; 04-09-2013 at 11:08 AM.