I have a set of 1109 69 430 heads with 64 cc chambers and lots of port work and money tied up in them. The block is a 70 SF 455 decked 020 and the pistons are BME forged flat tops with valve notches and yield 13.5 to 14 to 1 compression with this set up. So is there a forged dished piston that i can buy that will lower my compression ratio down to 9.5 or 10 to 1 so i can run it on pump gas. Thanks Billy.
Download the CR calculator from: http://webpages.charter.net/darrell1/dynamiccr.htm Play around with the piston cc number so that SCR ends up where you want it. Order some custom pistons with that cc.
I use common Fed/Mog 10:1 forged pistons (+.040" with 25cc dish, pistons cut .010", and TA eyebrows) slightly above zero deck with orange crush and aluminum heads (64cc). My block has been decked severly to accomodate. I use 92 pump gas and have no ping with 34 degrees fixed timing and TA510 cam. I figure I have under 11:1. Does this help you?
