I recently had to take off my resonator and noticed my afr on e85 change a little bit. Under wot it hits 11.8 11.9 around 4k then proceed to go to 12.5 12.6 these afrs are off an aem digital wide band, are these afrs safe or is a retune required

 

Your issue could also be related to the ethanol content. Have your Long term fuel trims changed much? That is a little too lean for my liking.

 

I don't really know I can't datalog it I just noticed that with my afr guage, the ethanol I filled up with recently was about 90% what should the afrs be under wot to be safe

 

they should no go over 11.4 11.3 if not less then that. i would have your tune looked out. I would also try to stay out of full boost. you may want to wait till the e85 is back and get it tuned on e85. no on winter blend

 

I don't think they have ever been that, I live in cali I got tuned at roadrace

 

r as e85 goes there's really not a winter or summer blend out here in California
Althought the levels of ethanol do fluctuate, I test at every fill up though

 

This is correct for gasoline but not E85. In my experience, along with what is suggested in the E85 subforum a good Gasoline AFR to run E85 at is 12.0 +/- .2 . Too rich and E85 seems to wanna knock.

 

AFR's at WOT should be between 11.5 to 12.2 depending on what your tuned for, ie road course, dd, or drag. What percent ethanol were you tuned on? If it were a true 85% and what you tested is 90%, that is enough to make you run a bit leaner.

 

I'm not too sure what percentage it was when it was tuned as I was not able to make it the day of the tuning, is it bad enough to have it re dynoed, don't want to re dyno just because of a resonator

 

I would hit up roadrace and explain it to them. Those AFR's might fly depending on your setup.

 

I was getting small counts of knock here and there with 11.5 . I kicked it up to 11.8 and it cleared up. Every setup is different though and you gotta find what the car likes.

 

Yea I think it was my gas I filled up today and were back around 12.2 12.3