I think I have created a possible ego problem here.. I have a 1969 Bird Vert.. I am trying to make a Trans Am Clone.. The heads are #48 close chamber high compression heads.. the block is a 400 cu. out of a 1969 GTO 4 speed with the build date two weeks after my car was born... The problem I have is did I do the rebuild with two low of compression pistons for what I have,???? The thing I'm afraid is it won't have the power or the torque and especially the sound... The guy that built my engine used 9 to 1 compression forged pistons, 30 over,, the heads were shaved 20 thousance to clean them up,, does anybody have an idea what horse power I will have and what the torque should be on 92 octane pump gas,???.. that is the reason for the lower compression pistons, so I could use pump gas.. also stainless valves... should I take out those brand new pistons and replace with higher comp. and a better cam,?? or will it eat me up for high octane gas,?????.. What would you guys/gals do,,????... I want to be able to cruise this mad machine and not have to rob a bank to do so,, but I want it all,, the best of both worlds, you know,, just like everyone else...
20 thousandths is 4 CC. Holding true, those heads were virgin at 72cc, you are now at 68 cc. Those pistons would have to sit in the hole pretty deep or have a nominal 18 cc valve dish/relief with a .020 deck.
Without throwing a bunch of crap at you. I need piston part numbers and deck height. Without those, all anyone is doing for you is guessing.
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1967 Starlight black PMD Engineering 400 Auto 1968 Alpine Blue 400 4 speed 1968 Verdoro Green 400 HO 4 speed 2013 1LE 2SS/RS Inferno Orange Camaro.
