Same dimensions as a 250 chevy for the DH and stroke.
80CC head gives 8.64 comp ratio
65CC head= 10.15 comp ratio
That is assuming the block will not be decked and have a .015DH( piston in hole.

Go to this website to calculate
http://www.rbracing-rsr.com/compstaticcalc.html

Assume a .041 gasket, 3.915 bore, 3.53 stroke.

I'd tell you to use the 80CC head, cut .030 from it. Cut the block appr .015 to zero deck it. Compression will be about 9.28.
This is with my 250 Ross pistons with 5.7 rod.

Inliner Member 1716
65 Chevelle Wagon and 41 Hudson Pickup
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