E85 Fuel in a track car?

[Spetz]

Hi everyone,

Just wondering if e85 fuel is a good idea to use in a track only car?

It's an NA car and I just wanted to bump the compression up a bit but I've read that the e85 fuel can cause rusting of the cylinder walls on cars that are not started frequently.

This car can go for 2 months without being started.

 

[Rat407]

I would use it at the track no problem but make sure to empty the tank at the end if it sits that long.

 

[spasm3]

Originally Posted By: Spetz

It's an NA car and I just wanted to bump the compression up a bit but I've read that the e85 fuel can cause rusting of the cylinder walls on cars that are not started frequently.

This car can go for 2 months without being started.


Are you talking about changing pistons to bump up the compression? How much compression ?

 

[NYEngineer]

Yep. Just make sure your fuel lines, pump, carb, whatever are all up to the task. It's a fine race fuel but as the others said, it needs considerations to sit. I think you can run it out and switch to gasoline at the end of the day before the engine is to sit for a while.

 

[Virtus_Probi]

I'm only repeating what I've read, but I know that FXT/WRX modders that run E85 will add a high capacity fuel pump as well as high capacity fuel injectors due to the lower energy density of E85 vs. gasoline.
Most of the insanely high output modded Subarus I've read about run E85, though. My understanding is that the high effective octane and cooling effect of the ethanol are huge in the turbo apps.
Good luck with your project!

 

[Spetz]

Draining the tank might be an issue as it needs to be at least about half full at the track given the corners.

I am unsure of what compression ratio I'd run (I am considering building a frankenstein engine) and depending on the available pistons I'd say 14:1 is possible

 

[andyd]

Install a fuel shut-off. Run the engine dry. Fog cylinders through intake.If you're worried about rust. Ive sorta done that with my OPE for the off season. Trouble is, my Toro runs on MMO.

 

[oldhp]

But the bad thing is E85 can legally be E51 to E83. So if you tune for E85 and get a batch of E55 you will lose out on power. Maybe in Australia they make them be closer on the mixture....here in the USA, they don't.

 

[BrocLuno]

Yeah, you'll have to d a specific gravity test with a hydrometer before final tune unless you can get consistent fuel quality.

If you are running a carb, run a return line and put the fuel pressure regulator at the carb bleeding all excess fuel into the return line. That way it'll keep the fuel cooler and more consistent, which is a bigger deal with E85 than straight gasoline.

Run the system dry at the end of the racing session, or just before you put it in storage. Use a squirt bottle to run the engine for a 15~20 seconds with some 2-stroke premix and shut it off. No corrosion issues then

If you don't have programable EFI, the carb jetting can get annoying for variable fuel quality ...

 

[Cujet]

Originally Posted By: oldhp
But the bad thing is E85 can legally be E51 to E83. So if you tune for E85 and get a batch of E55 you will lose out on power. Maybe in Australia they make them be closer on the mixture....here in the USA, they don't.


True. Of course, race spec E85 is exactly 85% ethanol. It can be found at some tracks and race fuel vendors. https://www.sunocoracefuels.com/fuel/e85-r

Quote:

"Sunoco E85-R is blended to consistently contain 85% ethanol. Conventional E85 can vary from about 51% to 83% ethanol or so but rarely contains 85% ethanol. Conventional E85 can also vary seasonally; the composition of Sunoco E85-R race fuel does not change. The non-ethanol portion of Sunoco E85-R is comprised of highly-refined race fuel hydrocarbons for stability and consistency. Sunoco E85-R is the racer’s fuel of choice where E85 fuels are allowed"

Note: I use E85 with regularity. Even here in humid South Florida, we have no rust or corrosion issues as E85 rapidly evaporates from hot engines.

Methanol is much more likely to cause corrosion of carbs and so on. E85 has nothing to do with Methanol's known issues. Some folks confuse the two.