BBC builders
I am looking for educated advice from BBC builders. This is on a 427 BBC. I rebuilt this engine earlier this year with the hopes of making big gaines in ET and have seen no improvement. The only things that were changed in the rebuild was the bore increased .010 to 4.320 and new CP 47cc domed pistons installed. The engine was 9.3-1 prior to the rebuild and is now 12.2-1. That is almost a 3 point increase in compression with no change in ET. Is my combination way off or could it be that my domes are severely limiting flame travel?
454 block bored to 4.320
3.76 stroke
6.135 H beam floating pins
CP custom 427 47cc pistons
assembly balanced
Solid roller cam, lifters and rockers, stud girdle
677/712 lift
252/262 duration @ 50
108 lobe center
102 installed centerline
stock Merlin Iron 320cc runner, 119 chamber rectangle heads with 2.3/1.88 valves
stock Team G 2" plenum intake
Pro-Systems 1000HP carb
Hooker 2" OD 1 7/8 ID headers w/ 18 extensions
Thanks in advance.