Fuel in the midwest 93 with ethanol or 91 octane with no ethanol ??

[mrbob]

would like opinions on todays fuel which is recomended for a modded gen1 thanks to all

 

[Viperless]

91 is the minimum. Go with 93.

 

[DrumrBoy]

I'd go with the 93 as well. Besides, given the vagaries of regional supply lines, even if the pump says no ethanol on the 91, I'd bet that some large percentage of the time that the underground tank IS filled with 91 octane with ethanol.

 

[uvbnbit]

what mods? N/A you'd be ok with 91, I think. PCM would make adjustments. If F/I, you'd need a 91 octane tune under boost (open loop).