i run 89, the way i see it is if the gas is watered down the worst i get s 87, if not im happy runnin 89.

 

Octane rating refers to the fuels ability to resist PREIGNITION !!!!!!!!! That in turns will cause knock , ping ,,,,,,,,,,,,,,,,,

 

Nope, octane rating is a fuels ability to resist ignition. Preignition happens when you put too low of an octane in an engine. If it was rated for preignition you would need a universal engine compression spec to test against for each octane, and that's just silly.

 

The word pre ignition means ignition that takes place before the ingition event occurs [ spark that is ] !!!!! Preignition is usually caused by hot spots in a combustion chamber or a severly over heated engine . The prefix PRE means before as is taught in elementary school ,,,,,,,, look it up . The hot spots can be caused by heavy carbon deposits , sharp edges , etc , etc adnauseum . The real benefit of high octane gasoline comes into use when high compression and advanved timing is used to enhance performance . I am not going to get into pizzing contest with you , the info I just offered is common knowledge to any well informed technician ,,,,,,,,,,,,,,,,,,,,


Gman

 

Nice reply...

Look, preignition implies a standard of ignition. You are getting hung up on the english here. I wont get into a pissing match with you either, nor will I try to add credibility to myself by saying I am a technition. Unless you are a gasoline technition, it doesnt mean jack.

The octane rating of gasoline tells you how much the fuel can be compressed before it ignites. When it ignites, that is ignition. To have preingition, you would have to have ignition correct? Yes, so when they test gasoline they compress it until it ignites. The measure of its resistance to ignition is its octane rating.

 

dang we gots us sum rocket scientist in here this thread is becomeing interresting

 

I am likewise not a technician, nor am I looking for a pissing match. I beleive we are saying the same thing. Whether the the fuel is resisting pre-ignition or ignition is all the same to the fuel. It's the engine which may have the problem with pre-ignition and thus would require a higher octane fuel. With the octane rating, what you are actually talking about is the fuel's auto ignition temp( the lowest temp at which the fuel will self ignite). Compresion of the fuel creates heat causing auto-ignition. Beleive it or not you cannot ignite standing fuel with a burning cigarette...it's not hot enough but a spark, even static discharge will do it (kids don't test this at home.. or anywhere else). If you want a really high octane fuel to run in your machine run diesel.
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I was joking about the VP race gas, calm down boys.