2007 Mustang GT w/Pypes Mid mufflers and Brenspeed 91 octane tune. It was running lean the first run, so we richened it up 4% for the second run and it could stand a bit more fuel still. I think I might've accidentally leaned the tune out when flashing the XCal once and not realized it which explains the lean condition.

 

Nice, how do you like the PMM, mine are on the way...

 

You're saying you had the a/f LEANER than 13.5? Personally I wouldn't have it as lean as you do I'd stick with 12.8-13.0 at WOT MAX. But that's just me I don't like possible detonation.

 

I love the sound and construction of the system for the price, but I'm having some rattling issues with it right now and I think it's because the welds weren't finished inside the mufflers. I'm contacting them today to see what they say about it.

 

I think when I was uploading the 91 tune from my XCal a while ago, I accidentally leaned out A/F 4% and then saved the changes to my unit. We richened up the mix but I'm going to do a nitrous kit next week and take it back for a retune.