Hello - I'm here in Upstate NY where the majority of our gas has the "Contains 10% Ethanol" stickers on them. When you find non-Ethanol pumps, the octane is usually 90 or 91. When I first bought my Spider Abarth (it still only has around 2500 miles on it!) I used 93 octane fuel with ethanol. The car was great! I did something stupid.... on a long drive I thought "why not try lower octane fuel??" because I didn't think I'd be using the benefits of the octane on the highway. Well, when I got to my destination, the vehicle definitely felt less responsive... less GET UP AND GO. So I decided to put in some octane booster and switched to non-ethanol gas. But I don't think (maybe it's just in my head) that using a 1/2 bottle of octane booster and running 90/91 octane non ethanol fuel is better than the 93 with ethanol I started with. I honestly haven't a clue. I'm not at all technical on any of this -- so I'm not sure what the best course of action here is. If you ask me, the vehicle today isn't as "peppy" as when I bought it and was using 93 ethanol fuel. What's the best for performance? What's the best for the vehicle? Is there such a thing as "too much octane"? I mean if I put 93 octane and then add 1/2 bottle of octane booster, is that too much? Just trying to figure out what the best thing to do is!!! Thanks for helping out a clueless new guy!!