E85 vs 112 octane gas

[rioredstang]

I just dynoed my motor with new header. I picked up about 6hp over 4-2-1 header. The guy doing the tuning on my computer ask if I have tried E85 fuel. I don't know anybody that runs it. He said it has more cooling effect and I can run more timing.

I think some of you are running E85. Is it worth trying?

[djsilver]

It will allow you to run more timing so there's some advantage to an NA motor, but not nearly as much as for a forced induction motor. It also has less energy per unit mass, so you'll need to run bigger injectors. I looked at it and figured I'd need to swap the stock 270cc injectors for the 340's just to make up the difference with an NA motor. E85 is also aggressive on rubber parts so you'd need to inventory the fuel system and adjust for it. Try doing a search on here and you'll find plenty of discussions about it.

[Seraphim38]

also, E85 isn't available everywhere. I live outside of Seattle and even thought there are millions of people who live here, and biodiesel is accessible, I would have to drive for more than a half an hour to get to the nearest source for E85. There's a gas station with Trick unleaded race gas only 5 minutes away...

[Def]

E85 vs. 112 octane is probably not that different in terms of performance on an NA engine. I'd imagine you might pick up a few HP, but it's probably not worth the time and expense to convert if you deem 112 reasonably economical to run. If you're going through 40+ gallons in an outing, then I'd say E85 would pay for itself and probably outpower the race gas when tuned well. Alcohols make great fuel really.

[AdamR]

I was just reading this in a thread on the Megasquirt forum.

We did some testing for Grassroots Motorsports on Kevin's Miata. It made 4% more horsepower and torque on E85 compared to 100 octane oxygenated race gas and had to use about 2/3 more fuel.

I know it's not the same, I just thought I would share.

[rioredstang]

I do have (2) cars that I race. I have a ITS & ITA cars so I will use close to that sometimes. I am going to run my ITS car in EP sometimes and drive both. I am checking on the price for a drum of fuel instead of by the gallon. I believe the octane would be more consistent.

[Def]

I do have (2) cars that I race. I have a ITS & ITA cars so I will use close to that sometimes. I am going to run my ITS car in EP sometimes and drive both. I am checking on the price for a drum of fuel instead of by the gallon. I believe the octane would be more consistent.

The cooling effect of E85 is so great that for an NA engine it doesn't matter if it's E70 or E85. In fact, the octane of the fuel stops increasing much after you get to 50% ethanol.

So no fears with getting it from the pump.

[Beejis60]

All this E85 talk makes me wanna do conversion on my POS....

One day.

[Tenchuu]

Last i read people had to increase fuel volume by about 30% when swapping to E85 from pump, so that is a lot of injector headroom that some may not have.

[rioredstang]

What are some prices in your area?

[Def]

I haven't priced it lately, but it used to hover about 20-25% less than 93 per gallon. Given it took exactly 25% more fuel when going from E10 to E85 (just as the chemistry would predict), it's roughly cost neutral when compared to 93, but a money loser if you're commuting in the soccer mom mobile with 87.

That said, the price varies by quite a bit compared to which area of the country you're in. I think it's a bit cheaper relative to high test gas in the midwest.