Brian:
To get 13 to 1 compression from your 302 is tough.
With 64cc heads and a typical .040" gasket and the piston .010 in the hole, your going to need about 23cc of piston dome.
I looked and did not see anything thats a "shelf" piston. Custom pistons are the only way to get that much dome.
You don't have much swept volume with the small stroke.
You stated that 12 to 1 might also work. About 18cc dome will get you 12 to 1.
I don't think you will see much power difference between 12 and 13 compression.
You have to get so much dome volume that it hurts the air flow from the intake ports and flame travel also suffers.
What you gain in compression you loose in efficiency.
Way back when, [showing my age] we used to angle mill those heads down to about 57-58cc chambers.
Then you can use a "shelf" piston and get more compression.
BUT [here it comes] you will find it way more user friendly to put a bigger stroke crank in it.
If your using this engine for sentimental reasons I understand.
Keep the block but put a 3.25 or a 3.48" stroke crank in it and have a better selection of parts.
You can still use the same rods and get 327 pistons or 350 pistons. Smaller dome, less cost and more power.
If your like most of us you can only afford to build one engine.
Thats my 2cents and thats all its worth!
Matt
