Quote:

a cheaper alternative might be to get a 4.15" cast stroker crank.

kb-silvolte.com shows the #1271 piston (for a 383) as a 1.848" comp height.

1.848+6.76+(4.15/2)= 10.683", or .042" in the hole based on the blueprint height of 10.725" for an RB block.

based on my calculations assuming a .040" head gasket and 88cc heads, you're looking at about 9.96:1 compression

use a largish cam or a wide LSA to make the intake closing point late to bleed cyl pressure, and it should run on pump premium.



better check your math
1.848 + 6.76 + (3.75/2= 1.875) = 10.483 - 10.725 = -.243
About 7 to 1 compression give or take