Until yesterday, I have always used just regular 87 Octane unleaded in my 1992 Mitsubishi MiniCab. On a whim, I filled up using Shell 91 Octane, and without paying really close attention, I began to notice that my little buddy seemed to be acting a bit different. - - Just more perky, and generally seemed to be more powerful, and generally in a really happy mood. I know this sounds a bit goofy, and I'm also aware that unless an engine actually needs it, using higher octane fuel will do nothing, but damn - - it actually seemed to make a difference. - - Enough that I think I'll continue to use the 91 Octane, even though it costs quite a bit more. - - After all, these things do get pretty decent mileage anyway, so the cost won't kill me. Am I just blowing smoke, or has anyone else found similar results?