My 2001 GTP does not have Performace shift. I have a couple of questions. Did GM just incorporate the perf shift into the operation of the transmission under WOT on the newer(after 2000) cars vs. the manual switch on the earlier cars?

Also, a new PCM modifies the shift points, firmness, 4-2 and 3-1 skip shift, etc. but says it only works in the the performance shift mode. What does that mean for me on the newer car without the perf shift switch?

I think you car doesn't have the button because it's built to always be in "performance" mode. GM did away with the normal mode.
I know that on my '99 the performance mode button is a waste of time because I always have it in performance mode. You're lucky...everytime I reach into that giant change holder under the ash tray, I hit that damn button putting it in normal mode.

I was under the impression that they did away with the performance mode...I could be wrong

I know what you mean Austin GTP about accidentally hitting the performance shift button. I usually leave it in normal mode until I really have to . For me, I guess it's because I used to leave it in performance mode until I had to repair my tranny a little over a year ago. I don't feel that I abused my car, I had no problems until, I got the tranny fluid drained. Anyways, don't mean to bring any negativity into this.

GTP Jack

Leaving Perf shift on should help with tranny longevity. Higher line pressures decrease clutch slippage extending clutch life. That's why GMP reprogrammed the computers to stay in perf shift all the time.

Thanks for the info HercMan, performance shift it is.

There is a pin you can ground out so Performance shift is always on. iirc its pin 21

I you ground the Performance shift on pin 21 will the performance shift light up on DIC??

I would imagine it did all the switch does is ground out that pin anyways.

I thought that the reason they put the perf shift button on there was so you could turn it off and save a couple miles per gallon on gas? Anyone else hear of this? Because of that I have been keeping mine off till it is hammer time. Now after reading about it improving tranny life, I might have to keep it on all the time.

Yes leaving it off will improve MPG. But so will driving like a normal person and staying out of the boost and slightly press the ole

Hello,

Question,
If the newer GP's are locked into Performance Shift, why would the reprogrammed PCM's not work on the newer cars?
After all, they are made to operate to their full potential in Performance Shift Mode.
The aftermarket PCM's come with a switch to let the PCM see the change in the newer models. I dunno, mebbe I missed something....Please educate me.

Later now,
Clint

Clint:
My original question started with that. I want to know if the PCM will be effective in all of the areas where it says," works in performace shift mode only".

To change the subject, how about a write up and detailed photos and instructions on how to build a sweet plexi cold air box like you made for your car. That is tight!

I thought that in order to put a reprogramed PCM ona car without the P/S switch U had to install one.

here you go..