drittal
Senior Member
Running premium won't help and will likely hurt a bit. unless you are tuned properly for the increased octane, you are wasting money.
Mainly I run the 91 instead of 89 because of 1 factor. The Exxon station I use the 87 octane is 10% ethanol, the 91 has none. The 89 is a 50/50 blend of the two. I've known the owners for years. They are like a second family.