Stonerracing

A gas station has just recently opened up by my house and i noticed they have 93 octane gas. Reading the sticker below, it said their is "30% ethanol" in it. "Use on flex fuel vehicles". My question is isn't this the wrong 93 octane to use on my csu gas carb?. Isn't there another type of 93 octane gas? Thnx

truckdoug

iTrader: (25)

yeah there is no way for the carb to adjust for the additional fuel volume needed when losing that much energy density


other types of 93?

we have ethanol free 93 here, for marine and small engine use

most 93 here is between 7% & 15 % alcohol blend. kind of a rip for the average joe. less energy for the buck.

and to top it all off, our local E85 station is more like E70 in reality

ya just cant win

forcd ind

iTrader: (7)

Around here we have 10%, what the Feds allow-they were going to mandate 15%, but I think it
got knocked down. My flex fuel sen. reads it as 8%. When I dump in 5 gals of E85 it takes it up to
like 24%, but I run a Holley HP, so it adjusts. You could prob call Kevin (csu) and he could advise
a jet change. Sure wouldn't use it in a small engine, lol.

Luke19901

30% ethanol content over o% ethanol content in normal pump 93 will require roughly 12% more fuel to maintain the same AF ratios. it needs 12% across the entire load/RPM range which should mean a simple jet change.

without a dyno or wideband AFR gauge on a quiet back road you could never be certain its correct for the extra ethanol content.
plus side is it'll likely take some more timing as the ethanol ups the octane