Thread: Need to lower compression on 454

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I have a 454 that is .60 over. I had it built about 13 years ago. But I have barely ran it. It is just a summer hot rod. It has chevy heads that are pretty modified. I have forged pistons and with the heads that are on it the compression is 12:1 I have always used race gas in it. But I have had it with the price of race gas and want to be able to run 93 or 94 octane. I know I can change the heads. Or pistons. I would really hate to do either. I have had people tell me to change the carb and run E85. I hear mixed opinions about that. Any opinions on the best and easiest way? I figure I need it below 11:1 to use pump gas. Anyone here use E85?

new pistons or e85 if you have alot of work in the heads you may want to go with pistons.is this a close chamber head now? if so you could put open chamber heads on it if the cam set up for hi cr then it not going to work good if you drop it to far down . i would be looking at e 85 if you have it around were you are .i have not see it here i have had 13to1 454 that i could run prem pump in it just to bang around town i had a big cam i allways used ave gas i think 101 LL ? thats been some time but i go to the air port with a can and i did mix it as well i do not know were the price is on this stuff but race was i think $5.50 at the pump here

There is E85 here and it is pretty cheap. About $2.00 a gallon. But can it mess up the engine? Octane is not much different. I run 105-110 octane race gas now. But I don't know much about E85.

Originally Posted by camaro man

There is E85 here and it is pretty cheap. About $2.00 a gallon. But can it mess up the engine? Octane is not much different. I run 105-110 octane race gas now. But I don't know much about E85.

you will need more of it so you need a carb set up for it and the engine may want a new timing curve plugs etc .i have not used it. i may on my next build will be over 14to1. dave Severson on here has used it he knows more about it then me