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Model 98 compression

Posted: Sun Nov 03, 2013 7:29 am
by rtboone
Hello all
Can anyone tell me what the correct compression for a 98 Super Rat should be with a fresh top end?
Also, can I use pump gas, or should I use race fuel or possibly AV gas?

Thanks

Tom

Re: Model 98 compression

Posted: Tue Nov 05, 2013 4:36 pm
by Bullfrog
. . . somewhere around 150-160 psi.

You have several options - premium pump gas (Ethanol free) if you can find it easily, race fuel, race fuel/premium pump (non-ethanol) blend and yes, even aviation fuel. Though aviation fuel probably ought to be your last choice - it is designed to burn somewhat more slowly than auto gas, so won't perform as well as the other options listed above. It is however a usable option if race fuel feels too expensive and non-ethanol pump gas can't be easily found in your area. Note that there is a web site which lists where straight auto gas is available in every state.

Ed

Re: Model 98 compression

Posted: Wed Nov 06, 2013 2:00 pm
by rtboone
Thanks Ed

I did a compression test and came up with 148 lbs. I assume that the number will come up a bit with a little running time and the ring gets seated,which should get me into the 150-160 range.


I also found that site you mentioned, and if anyone is interested, it is "www.puregas.org". Just click on your state to find vendors of non-ethanol fuel.

Tom