I dragged this over from the SBM flow number thread.
I didn’t cc the runner.
This particular set did not get any cnc work in the chambers…….they were as cast.
CNC’d SM head-
OOTB vs valve job with back cut valve, and minor blend-
28” test pressure, 4” bore:
A-OOTB
B-Valve job
Intake ports:
Lift———A/B
.100— 64/67
.200—126/132
.300—166/191
.400—206/232
.500—242/262
.600—271/275
.700—284/281
Exhaust ports:
Lift—— A/B
.100— 49/55
.200— 95/102
.300—132/137
.400—163/170
.500—179/188
.600—187/192
.700—190/194