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Is this REALLY necessary?!

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Old 08-11-2002, 11:07 PM
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Is this REALLY necessary?!

I was talking to a friend the other day, and he was telling me about how one of his friends has a 69 camaro and put a 502 in it. He started talking about how this kid has 130 something octane fuel that he puts in it. Is this REALLY necessary? I thought the basic purpose of octane was to prevent detonation. Is that much octane really necessary?
Old 08-11-2002, 11:13 PM
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i dont think its necessary. i know a guy with a blown 502 i nhis truck and he runs pump gas. i drove in it today and it seemed t orun fine.
Old 08-11-2002, 11:17 PM
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Would there be ANY reason to have this much octane? I'm under the impression that, as long as there is enough octane to prevent detonation, additional octane isn't a "treat" and doesn't improve performance. Is this true?
Old 08-11-2002, 11:24 PM
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if you run an insane compression ration (ex 13:1) you would have to run pretty high octane. but i still dont even know about 130.
Old 08-12-2002, 01:19 AM
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Originally posted by demonkey36
Would there be ANY reason to have this much octane? I'm under the impression that, as long as there is enough octane to prevent detonation, additional octane isn't a "treat" and doesn't improve performance. Is this true?
Yes, you are correct. Some people still think it's the octane that gives the power. He's just wasting his money. It's possible it could even be causing carbon to build up in the cylinders.
Old 08-12-2002, 04:53 AM
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what would the octane do to make carbon buildups?
Old 08-12-2002, 06:35 AM
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You are correct. Just enough octane to prevent early detonation. Any more is a waste of money.
Old 08-12-2002, 09:46 AM
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I've actually witnessed slower 1/4 mile times with race gas! It burns slower. Aren't most 502's like 8.5-9.0 compression?(man unless he has a heating prob or his timing way to high theres no way it would detonate on premium. Why waste the money? Prob Joe Big the biggest motor,the highest Octane fuel,high dollar plugs and wires,The most expensive oils,price means everything.... To each his own!
Old 08-12-2002, 09:59 AM
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Originally posted by demonkey36
what would the octane do to make carbon buildups?
Some high octane chemicals, "aromatic" compounds in gasoline such as toluene, xylene and naphthalene, have octane ratings in the mid 120's. Because of their structure, these chemicals are more stabil than others in the gas. This is what makes them more resistant to detonation. However, they also have a tendency to form lots of soot when they burn. Therefore, using them too much can cause the soot to build up in the cylinders.




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