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Old 01-02-2008, 07:22 AM
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bwilson4web bwilson4web is offline
Engineering first
 
Real Name: Bob
Location: Huntsville, AL
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Default Re: How to Blend Your Own Fuel, and Why You Should

Quote:
Originally Posted by chesterakl View Post
There is a popular myth that higher octane in fuel gives you additional power - it does not. Premium gasoline has the exact same energy content as regular (about 111,400 BTU's per gallon).
Sometimes it doesn't. My testing in Huntsville indicates three brands, Shell, Exxon, and Chevron, appear to have about 11% more energy in their 87 octane gas than the other brands, Conoco, BP, Texaco, and Citgo. The lower energy brands have the same energy content as the better brand, 93 octane, Shell and Texaco.

Quote:
Originally Posted by chesterakl View Post
The ONLY thing the higher octane is needed for is engine knock. High-performance engines are more sensitive to the octane level because they have higher compression ratios, so they tend to knock on lower octanes.

Plus, the computers in today's engines also detect knocking and will adjust the spark timing and other settings to control it.
I was able to see this in my gasoline testing at the higher power levels.

Bob Wilson

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