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Old 01-07-2013, 03:24 PM   #25
xwd
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It's absolutely cylinder pressures which require higher octane...

Spark advance can cause detonation, but the reason you have to pull back timing is based on cylinder pressure, whether it's a NA or FI application.

87 octane fuel doesn't burn correctly with higher cylinder pressures and spark, it explodes, which causes detonation. To say you could tune a car for 87 octane and get the same amount of power as a car tuned on 93 is completely incorrect.
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