E75 on E85 tune?

[MG0h3]

So when I made the conversion my station had E85 in Jan. Thought I would test and see where I'm at this winter and I got E75. I know I'm actually richer but the octane may be a little lower. Should I get a tune adjustment? Car still runs awesome. @04sleeper

 

[gt347mustang]

Negligible differences.

 

[MG0h3]

Ya doing some more research and it looks like E85 is 109octance and E70 is 105.

 

[bb83]

Even more so the listed octane and the actual is usually a little off....

 

[MG0h3]

Ya Im not going to sweat it unless Kevin chimes in and says we should adjust.

 

[04sleeper]

E75 won't really hurt anything except the fuel trims may be a little off due to the Stoich being a hair higher. I can always send you an updated tune file for E75 to help fuel trims stay in line. Octane really doesn't start dropping off until around the E50 mark so you have PLENTY of Octane.

Shoot me a quick email and I'll send you an adjusted tune for E75.

 

[MG0h3]

Awesome Kevin thanks. Email sent.

 

[NVRL8TE]

Man. I wish I'd of known I was good on E75, on my E85 tune.

I was so scared, I put my car away a tad earlier than usual this year.

 

[MG0h3]

Thanks again Kevin!

Guessing I got all the 85 out and was down to just the winter E75. Noticed the car was starting a little harder--slightly extended crank. Opened the glove box and sure enough; WB showing @12:1 at idle.

Threw the E75 tune in. Fired up like stock and 14.64 at idle.

 

[04sleeper]

Good to hear!