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This is confusing....?
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Posted by: tgreenz400

Well i plan on bumping my 400 up to a 426 or 440...the only problem that i see is that i think the stock compression is 11:1 but i think most pistons are high compression which is like a 12:3 or some thing like that...does that require race gas?

Posted by: cataway

race gas , no, but you should use 93 pump gas

Posted by: tgreenz400

quote:
Originally posted by cataway
race gas , no, but you should use 93 pump gas

k thanks

Posted by: TheNewn

Look into the Athena 434 kit.

Posted by: bloodmoney23

quote:
Originally posted by tgreenz400
Well i plan on bumping my 400 up to a 426 or 440...the only problem that i see is that i think the stock compression is 11:1 but i think most pistons are high compression which is like a 12:3 or some thing like that...does that require race gas?

if stock is 11:1 then at 13:1 you would want to start running race fuel. 12:3, would be the same as saying 4:1 which would be a low compression piston. but any piston you buy up to 13:1 just run 92 or 93 octane whichever your local carries. 13:1 up to 13.5:1 you could get away with 93 with octance booster. anything above 13.5:1 you will def need race fuel.