I have an 07 Tungsten GT premium with a K+N filter, Summit Racing O/R H-pipe, super 10s flowmaster exhaust and an SCT tuner with a 91 race, 89 performance and 87 street. I have had the tuner since October and have really only used the performance tune. Just plugged the race tune up and adjusted top speed and max rev driving. When I got on it I noticed a really rough shift at about 5k rpm almost like my car was stuttering. It doesn't do this with normal driving just at higher revs. Anyone have this problem or any insight into what is causing it!?

Also I ran the tank down and put 93 Octane in before I changed the tune

 

Did you reset it to stock before reprograming? Also, I don't have an auto but from what I understand the race tune basically has your tranny "dump the clutch" when you beat on it. It gives you the fastest, firmest shift as safely possible. Reset to stock to try to diagnose, that's what I'd do...

 

Thanks Muscledom. I will try that. It is actually a manual and I don't notice the firm shifts at lower revs just at higher ones above 5k, when I pushed it to about 6500 it actually didn't sputter or hesitate at all.

 

Well **** dude that's weird lol. You got me man. That's strange. But I'd definitely reset to stock and re flash it. The "firm shifts" kinda threw me lol.

 

Is it me or are u not supposed to rev that high anyway...? I was under the impression A. U are loosing power at that high of a rev B. I think max is 6200 rpm why run past it and take a chance on messing your motor up???