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87 octane 100% gas vs 93 octane with ethanol

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Old 03-11-2013, 02:30 PM
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87 octane 100% gas vs 93 octane with ethanol

I was wondering which one would yield better performance in my small block seeing as how I can get 100% gas in my town......I currently run the 93 with ethanol
Old 03-11-2013, 02:55 PM
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Re: 87 octane 100% gas vs 93 octane with ethanol

Depends on compression ratios and cam but i would feel confident in 93 oct over 87 for pure power.

If low compression deal then likely dont need 93 oct. Use least amount of octane as required to keep motor out of detonation with reasonable timing. Spark plug heat range and timing can bandaid too high comp for gas so you would want to look at exhaust temperatures and power output
Old 03-11-2013, 04:56 PM
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Re: 87 octane 100% gas vs 93 octane with ethanol

There was a brief blurb here.
It may or may not interest you.
http://www.ccfbg.com/forum/viewtopic.php?f=1&t=14401
Old 03-12-2013, 04:15 AM
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Re: 87 octane 100% gas vs 93 octane with ethanol

If you want an 11:1 or power-adder build, then 93E.
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