i think ron owens said at one time he had great luck at 10:1 compression.
i have ran it at 14:1 compression and found increased Tq..
Murff is right it likes a little more compression..sort of more is better theory but you will see benefits at the lower CR also
you will also get a wide variety of the maintenance of alcohol vs gas..
what are you looking to gain (expect)..i guess the Order has to suit the bill.
also just to put this on the table..the most economical /less hassle way of increasing your CR is to have the heads angled milled..if you motor is a candidate...
Several builders on here that can help you with advise to doing the work for you.
Brian
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Bjuice..
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