What is the biggest forged dished piston i can get for my 455. Its bored 38 over and i need the biggest dish that i can get in order to lower my compression. Its almost 14 to 1 now with flat tops and i would like to get it down to 9.5 or 10 to 1 so i can run pump gas. :TU:
Billy What are your deck and head milled amounts. I had a set of buick forged that were almost flat except for the valve clearance tray with .10" deck and .15" off the heads and still ran 93 octane @ 30* timing. No knocks! Are you using the standard compression ratio calculations to determing 14 to 1??? When I looked in the book at the machine shop there are 2 dish depths for factory pistons as I recall .156" depth and another around .196". You can have custom pistons made for about 100.00 a hole with anything you want. If your deck heigth is at -.005 and .15 mill on the heads as mine is, the Speedpro forged 8.5 to 1 ratio comes out to be 10:5 to 1 right on the dot. I run gas 93 octane and in the mid 11's @ 114 MPH. No knocks. timing set @ 30* to 32* total. Weekender :Comp: