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430exer
03-20-2006, 05:59 PM
With a 440 kit with 12:1 compression can you still run 93 octane?
GPracer2500
03-20-2006, 06:22 PM
Nope.
430exer
03-20-2006, 06:28 PM
what about a 11:1
Wheelie
03-20-2006, 06:47 PM
11:1 is said to be marginal, if you're set on pump gas, personally I would go w/10.5, just to be safe,
430exer
03-20-2006, 07:04 PM
Do you know a web site where I can find a 10:5 cause all I can find is 12:5:1,12:1 and 11:1?:confused:
GPracer2500
03-20-2006, 09:25 PM
JE makes a 10.8:1 89mm piston. Their 06' catalog lists it as a new item. That's the lowest compression for that size that I'm aware of.

I've found even 10.8 to be marginal on 91 octane. I'm guessing with quality 93 gas you'd be ok. [shrug]
QuadJunkies
03-21-2006, 12:49 AM
I ran the 11:1 in my 426 for 1.5 years-NO PROBLEM running pump gas.

I now run a 12:1 and half to run 50/50 mix in my 440ex.