I just installed the superchip micro max tuner on a friend's 04. We set it for the 87 tune, left all the shift points and pressure where they were, changed his gear ratio to 3.55's, changed the tires to 33's, zrated tires and raised the limiter. on his way home from work he got on it to see what the difference was and instead of it cutting fuel at 100, it does it at 90.

anyone have any idea what this is, he's going to reinstall the tune and see if that helps, but i'm kinda lost...

 

this is on my truck.. i re-did the tune to make sure i didnt miss anything but i still get a really bad fuel cut at 90mph at WOT. I thought maybe it was the gear ratio, my truck came with 3.55's new, so i went back and put the gear ratio at stock instead of 3.55 the 2nd time around and still got the same result. Could this just be because of the 87 tune?

 

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