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Ooh! Ooh! Pick me! Pick me!!

OK, here we go.... Since I was this close to buying a motor with a 13:1 compression ratio for my Olds, I got to do a LOT of homework on fuel additives, ESPECIALLY the octane boosters. I will set forth my considerable findings now, some of which most of us already knew, some of which we didn't....

First: For those who don't already know, using premium fuel on a car that doesn't specificly ask for it is a waste of money, and does more harm than good. The reason is very simple: Octane has nothing to do with a fuels quality or power potential, it's a rating of a fuels burn resistance. The higher the octane, the HARDER it is to ignite the fuel. Thus, a car with a normal compression ratio of under 10:1 and no boost gains NOTHING from using this fuel, unless you have an aftermarket chip that advances the spark to a frightening degree. Using higher octane fuel in an engine that doesn't need it will result in LESS power, and WORSE fuel economy.

Second: Octane boosters are, for the most part, a sham. I have read numerous independant tests, and the results are all the same - products that claim to increase octane ratings "4 to 7 points" actually raise the true octane .4 to .7. Yup, less than one point when used in the recomended dosage. Enough perhaps to eliminate knock in a finicky engine on a temporary basis, but not enough to do crap for a high performance, high boost or high compression engine. The BEST octane boosters tested managed just over 1.5 points of actual octane increase. Conclusion: If you really do need octane higher than what most pumps sell, find a spot that offers unleaded 100 octane (usually between $3.00 and $4.00 a gallon) at the pump, find a VP Racing Fuels dealer (they have several offerings ranging from 96 to 103 octane available in 1, 2, 5, 12, 16, 36, and 55 gallon containers), or mix your own, using tuelene or similar additives to get what you want - but you need to do a lot of homework to do this right.

Other stuff: Various other additives claim to do other things ranging from increasing mileage to cleaning different parts of your motor. There are always tradeoffs; stuff that effectively cleans hardcore deposits from the combustion chambers and injectors is also TERRIBLE for various sensors and downstream components, use it RARELY (read, every 50,000 miles at MOST, only when needed). Mileage increasers have a number of ways to accomplish their goals, one of the more common is to include a chemical that tricks sensors into thinking there's more fuel in the mix than there is, making it run leaner. NOT a good idea if you drive your car hard!

Hope this helped.... :)
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