Is it worth it?

Is it worth upgrading my GP's PCM if it doesn't have a performance shift?
Will there be any performance gains by doing it?

Is it worth upgrading my GP's PCM if it doesn't have a performance shift?
Will there be any performance gains by doing it?


Yes it will add the performance shift option

Catz,
Doesn't he have to add PS shift knob or a switch? If not won't it be on all the time?
http://img.photobucket.com/albums/v425/kustomkid54/1998PontiacGrandPrixGTP004.jpg

Wait, I'm confused...
The advertisements for the reprogrammed PCM say that the skip shifts, shift points, and fluid lines will only adjust if the car is in "performance shift mode". Can my car get into that mode if I don't a performance shift button?

Wait, I'm confused...
The advertisements for the reprogrammed PCM say that the skip shifts, shift points, and fluid lines will only adjust if the car is in "performance shift mode". Can my car get into that mode if I don't a performance shift button?


YES! it will add that option to your Car!

this has come up a few times now he will have to add a perf shift button or switch to enable that mode or with a jumper it would be on all the time and i wouldnt recommend that

this has come up a few times now he will have to add a perf shift button or switch to enable that mode or with a jumper it would be on all the time and i wouldnt recommend that


why wouldnt you recommend that?

Mine runs all the time...no problems

You have to read the part of adding a reprogramed PCM. Which will give him the PS without a way of controlling it. Now does this work?
http://img.photobucket.com/albums/v425/kustomkid54/1998PontiacGrandPrixGTP001.jpg

ok.. so what's the downside of continuously running the car in performance shift mode? gas mileage? added wear and tear to parts?

ok.. so what's the downside of continuously running the car in performance shift mode? gas mileage? added wear and tear to parts?


none....in fact my computer has it coded in without the Per. switch....so I dont even need to ground the switch

The down side, if you want to call it that, is a less "smooth" ride......and based upon the number of older women I see driving GTPs (what a waste) there's a lot of drivers who want a soft, smooth ride.

I was always taught that a firmer shift is actually healthier for a transmission that the traditional soft, mushy shift. When the trans shifts, there's a controlled amount of slippage, resulting in the smooth transition from one gear to the next. A shift kit and/or reprogrammed PCM reduce the amount of slippage, resulting in a firmer shift.

When adding a reprogrammed PCM you have three options:
1) Run a jumper wire from pin 21 to ground - this will result in Perf. Shift always on.
2) Run a jumper wire from pin 21 to a toggle switch mounted on the dash or console.
3) Replace your shift knob with a pre-'99 shift knob with perf. shift button. Run a jumper wire from pin 21 to new knob.

You guys have to keep in mind that Catz has a lot of custom stuff done to his car.

And I'll bet its those old ladies who caused the performance shift to be removed from the GP in the first place. I guess I don't have to look far, since the former owner of my GTP was a mom with 2 young kids. What a waste.
At least the potential is there to bring it back.

Thanks guys

Cass,
I love it when you get techical. Those big words.
He's acouple of things that might help.
http://www.grandprix.net/upgrades/pcminstall.html
http://www.rivman.com/perfshift.htm
I know you had everything that was needed, but mine took less space.
Now for my 8x10 photo...
http://img.photobucket.com/albums/v425/kustomkid54/1998PontiacGrandPrixGTP004.jpg

i wouldnt reccommend it because i would think it would kill fuel mileage and with the line presure increased on the tanny i would think it would shorten its life

i wouldnt reccommend it because i would think it would kill fuel mileage and with the line presure increased on the tanny i would think it would shorten its life


Wrong on both accounts......in some cases it will improve both of the above

Thanks for the links Kustomkid, but just one question...
Does it matter if my GTP's an '03? The instructions seem to imply that they don't cover GP's newer than '02.

Thanks for the links Kustomkid, but just one question...
Does it matter if my GTP's an '03? The instructions seem to imply that they don't cover GP's newer than '02.


Instructions work for all GPs through 2003

We make a good team, don't we Chris?
http://img.photobucket.com/albums/v425/kustomkid54/1998PontiacGrandPrixGTP001.jpg