Rpm 340 Cyl heads on a 318 !

FWIW for the Chevy rod + pistons combo..... Here is one combination that might work with the 318 if you can bore to 4.00":
  • Icon forged 4.00" pistons IC792 with CH=1.678", Flat top with 2 valve reliefs
  • Then use a 6.300" long Chevy rod, with 2.100" rod bearing.
  • Grind down the SBM crank to that bearing size, and offset the center +.0125" higher.
  • Resulting piston to deck height would be +.045" (if I computed it right) and with a bit of block decking, you can adjust that for a .035' or .040" quench gap.
  • If you wanted even more CR, the the IC793 forged piston has a dome that can be massaged down a bit for whatever you might like.
WOW - what a combination !!
The destroked crankshaft I purchased is Extremely unique to me because it is
new in the box and was one of Bob Gliddens crankshafts from when he run a Dodge .
The guy who sold it to me did note that crank could have GM rods installed on it with a little work so your RECIPE is inviting!