the target afr's depend on the setup and the conditions. 11.5 is a good starting point and then either go a bit richer or leaner from there and see what works.

 

just be careful. My AEM AFR wideband was off compared to my tuner's Dyno Wideband gauge. He tuned my car on the dyno at 11-11.5 WOT, but my AEM always dips into 10's. I tend to trust his a little more.

 

Great comment. All widebands read a bit differently. The sensors we're using aren't really 'lab grade' nor are the conditions we're using them in lab conditions. Stick with your tuner's tune unless you're willing to take responsibility for breaking your car.

I tend to stick to 10.5 to 11.5 AFR at WOT under full boost. I would rather loose 1-2% horsepower and keep it safe than give up that safety margin and blow a motor due to bad fuel or fuel system problems.

Tim

 

I talked with him today. He said I made teh same power @ 10.5 as 11.5 so he put me richer to keep it safe, and teh extra fuel will help with cooling....

Tomorrow we're bumping up the boost a bit and making sure everything is still safe @ 18psi.

 

no reason to be that rich. 11.5 - 11.8 would be more acceptable.

good luck man.

 

I run 12.2 with my comptech aftercooled setup but I'm only running 7psi of boost.