Running a 60/40 fuel mix (93/e85) with GIAC race tune

[simplymuzik3]

Hey everyone,

I've seen a few people post here and there about running a mix of e85 with 91/93 and using their race tunes (designed for 100 octane). I checked some online calculators and it comes out to around 97-98 octane with the blend. I have a stage 2 AWE/GIAC tune on my DSG (including DSG tune). I'd love to at least try out the race file, but don't want to damage my engine. I wouldn't be running it all the time, but I think it would be cool to try out every now and then.

Thoughts?

[infinkc]

You are fine.

[q5 dave]

It's fine. Halfway through a tank of 93/e85 mix on my GIAC stage 1 3.0T Q5 running race mode. Its awesome. Idk about 60/40 mix though, it might run lean and throw a code. I did 36% e85

[pdqgp]

I would verify with GIAC before you do it regardless...

[S-Fore]

Good advice I push 38%, and if I get the lean code, I add another gal of 93....happened once. I'm on my 4th consecutive tank. I just calculate at the pump and keep the correct %. Luckily, I live 1.5mi from a station that sells E85...

It's fine. Halfway through a tank of 93/e85 mix on my GIAC stage 1 3.0T Q5 running race mode. Its awesome. Idk about 60/40 mix though, it might run lean and throw a code. I did 36% e85

[jazza08]

A 60/40 mix will give you ~98 octane so it's not completely safe to run a 100 race tune and whilst the ecu will try to compensate for the e85 its not tuned for it and the pump struggles. It's not something I'd recommend doing on a regular basis but run some logs and see how you go if you're that keen.