2004 Malibu Fuel Type

Would there be any advantage, or disadvantage in using high octane gas rather then the reccomended regular gas? What if I used high octane every month or so? If cost did not matter would I gain anything by using the best gas? Thank You Bob

I use the medium grade gas and that seems to give me the most power and mpg for that tankful. I also fell a HUGE improvement when i am flooring it the car acclerates much faster

was reading on the gov't site for fuel economy http://www.fueleconomy.gov/ they said you only really need to use higher octane if you engine knocks..makes like a clanking sound when you drive. and something else about how all fuels, no matter what octane, are required to put things that prevent engine deposits

Higher octane gas is for engines with high compression. With lower octane gas in high compression engines, the gas ignites during the compression stroke before proper combustion, damaging your engine. Higher octane gasoline takes care of this problem. On a car such as a Malibu, there are no advantages to using higher octane whatsoever. Stick to the lower grade gas. It's cheaper anyways.