[F3XX]

I just wanted to see if anyone has ran any e85 on a stock M3 or M4 and if it is safe to do so.

[SickGTR]

Originally Posted by F3XX

I just wanted to see if anyone has ran any e85 on a stock M3 or M4 and if it is safe to do so.

Wait to get some kind of tuning for the cars.

[sleepy75]

Owner’s manual says you can run up to 25% ethanol.

[mike@x-ph.com]

Originally Posted by F3XX

I just wanted to see if anyone has ran any e85 on a stock M3 or M4 and if it is safe to do so.

A Low mix is safe but you get no benefit from doing so without a Jb4

[BadBoostedBMWM3]

I've been running a calculated 25% since the first fuel up, and it feels good.

I did fuel up with 92 on the last tank and my butt dyno feels less, but I'm probably just off.

[brad65ford]

Was wondering this to since the f80's loved 2-3 gallons on stock tune mixed with 93 octane

[FC4]

Can likely mix in 2-3 gallons per tank with no harm whatsoever.

[Taiwanboikia]

i just tested today with Dahler tune. E10 vs E30 was 50whp difference

[Taiwanboikia]

what i am more wondering about is what is the highest Ethanol that we can run on stock fuel pump. I do have the fuel it kit and can see the E level.

[Likeanowl]

Would mixing in a couple gallons with no mods at all be safe long term? I have a station that sells e85 at the end of my street. If it’ll run safely I may start adding that in on every fill up.

[somer]

maybe easier to just run octane booster?

[TopJimmy]

Originally Posted by somer

maybe easier to just run octane booster?

Ethanol is way better than octane booster. Booster leaves orange residue powder all through your exhaust, and it can clog O2 sensors.

To hit E20 use 2gal E85 with 12gal E10 gas.
To hit E26 use 3gal E85 with 11gal E10 gas.