New to the forum 2005 Acura Tl at
 

I have a 2005 Acura Tl and my sister has a 1998 Mitsubishi mirage DE at. Im currently with my gas guzzler..lol but as soon as I sell it i will be on the lookout for and Honda civic hx! I have a question if anyone here has tested it. If I run regular in my tl will gas mileage stay the same? I drive very moderately and dont even hit vtec anymore so regular should be ok but before i make the jump i'd like a second opinion :)

Welcome! As to your question about octane vs mpg's In my experience with my cars it depends:D my Maxima, Altima, and Celica were/are very sensitive to premium gas. My F150, Suburban, Towncar, didn't care what gas went in them. Talking about 10% or so differance.

Thanks for the info. So 10% decrease in mpg with regular. But i believe all the cars you mentioned take regular gas right?

They all ran ok on regular, the Maxima was the only one with a premium recomendation, but it also had the most dramatic changein fe. All three cars I mentioned run better and have more power with premium. The cost differance between premium and regular is typically only 20¢ and I found that the fe savings would more than make up for that.

Ok so I put midgrade and drove like a grandpa grandpa and was able to get 37! That is crazy i never knew that would even be possible out of this big of an engine and car.