Reply to "Octane vs Compression Ratio..."

doug s. (Guest)

my stock 8.6:1 cj engine runs yust fine w/87 octane. as i understand it, running higher-octane gas will actually cause the car to run *less* well, as the slower burn characteristics of the higher-octane gas may cause incomplete combustion.

i'm getting parts together for a closed-chamber 4v head motor, w/a mildly hotted-up cam, flat pistons, & ~10.5:1 compression. again, i understand that i will be ok w/93 octane pump gas, because the "squish" area caused by the quench heads aids in more complete combustion, & the hotter cam will actually reduce the compression at the beginning & end of the firing cycle, due to the greater walve-opening overlap...

5/15/011:25 PM

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