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Old 09-13-2007, 11:49 AM
juribe2 juribe2 is offline
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Join Date: Dec 2006
Location: Colombia
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Quote:
Originally Posted by G-Benz View Post
..... Translated, it takes a higher temperature to ignite the atomized fuel in the combustion chamber. That means, it won't "pre-ignite" in the compression cycle or "knock" as what it is normally referred to.

This is why turbo gas engines require premium.
It's not about temperature. It's about compression. Higher octane means it needs more compression to ignite without a spark (pre-ignite). Using higher or lower octane depens on engine compression relation and hight above sea level. You need high octane when at sea level and can use (or mix) lower octane on high locations. Engines with compression relations under 10:1 usually work good with regular fuel.
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