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Old 07-18-2008, 02:24 PM
automotivebreath automotivebreath is offline
Oil Changer
 
Join Date: Jul 2007
Location: Southern Louisiana
Posts: 444
I have done extensive experiments with high compression low octane engines. I find
that it's very difficult to realize any benefits from an increase in compression over the
ratios that David posts "89 octane for 9.5/1 Dart headed motors. On 10/1 -11/1
compression engines we have used premium"
. Anything above this normally
requires some sort of compromise like lower water temperature, reduced ignition
advance,late intake valve closing and or richer air/fuel mixtures. Not worth the
trouble IMO.
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