My car is running about a point lean when it's cold out (high 12's at WOT instead of high 11's). The tune is spot on when it's warm, but when it gets down to 50 or so it leans out. This seemed to start after switching to E85.

I found a MAT Correction table that was zeroed out in the tune. It seems easy enough to just add 10% fuel at 50 degree MAT but wasn't sure that was the correct way to adjust the tune. Is there another method I should be trying or will that work?

 

That's pretty much how I'd tune it.

flat across in normal conditions, then altering it when you are outside the norm and need corrections.

 

Awesome, thanks. That just seemed too simple to be correct.