Re: 93 octane in stock engine
Yeah, the 93 octane is "more difficult" to burn. The only reason I see to use it is to avoid detonation, which you would get in higher compression engines by using low octane fuel (since the lower octane fuel, which is more volitile, ignites too soon in the higher temperatures of a high compression engine). In the 2 stroke engine world, you can run up to about 180-185 psi on 93 octane - after that you have to go race fuel to avoid detonation. Not sure if that translates to the 4 stroke world or not, but I would assume it does.
1995 YJ 4.0 5spd, 3" body lift, 32" Bridgestones (w/damn 3.07 gears), Durabak