I have my X MR-T running on E85 like a bat out of hell with a AFR of 12.1 (gas scale) WOT from 4000-7000RPM. I have been working on increasing the MPG so I've changed the midrange fuel and timing tables a bit and I'm working out the ramifications of these changes.

Anyway, yesterday I floored it in 6th gear at 2500rpm, something I never nornally do, and the motor exhibited just a bit of rough vibration and an AFR of ~15 at WOT (but no knock counts)! This condition can easily be avoided by simply not "punching it" below 3500 but I would like a more elegant solution and I am not sure which table I should look at (I am very much a novice at ECU tuning). I have not logged this condition yet as to not abuse the motor unnecessarily so I do not know what load cells or boost I'm hitting when WOT at 2500RPM.

 

Mostly likely, you're getting compressor surge.

 

Hmm where to start...first off you probably shouldn't be trying to eek every last mile out of the tune if you're on E85...if you wanted a fuel efficient car you should have stayed with a pump gas tune. Second, why would you ever punch it WOT at that rpm in 6th...the car is going to be moving no where fast at that rpm without downshifting. Do you have a log showing that it wasn't knocking? because I'd almost guarantee it was knocking if your AFR actually hit 15:1. Even on E85 or race gas anything over about 12.5:1 is sure to be knocking.

How many psi are you tuned for? What injectors are in the car? Hopefully not stockers/stock fuel pump.

 

Did you even read my post? I stated I did not log or know what the boost was at the time, injector size is DW1000cc. I know it was not knocking as I was watching the knock sensor on the AP and it showed 0.00 counts during the event, what I am not sure of is that my wideband correctly reported >15afr, conditions could have been eratic enough to throw off the afr sensor breifly and I am not prepared to repeat this abusive behavior. Why tell me what you think I "shouldn't" be doing? Help me achieve what I'm trying to do, let us help each other here, not lecture and provide unconstructive criticism.