Some GTP's came with a feature called Performance Shift.
It's a second set of shift tables in the PCM that use higher shift points (and maybe raised line pressure, can't remember). There is a button on the shifter to switch back and forth between the Performance Shift and regular shift settings.
From what I understand, all of the L67 cars have this feature in the PCM. It's just a matter of wiring up a switch to make it useable.

Take a look around some of the GP sites/forums, there is enough good information on some of them to make your head spin. Worth the time to research imo.

Good luck with the test drive. I can honestly say I wouldn't commit to buying any car without test driving it, so I wish you the best.

-Riggs.

 

Just an on/off switch on the shifter that makes the pcm use a different set of shift tables, as mentioned above. Honestly, in stock form, its not very impressive- not even really noticeable to someone who doesn't pay a lot of attention to the car (my wife DD'd my old GTP for over a year- and she'd occasionally bump it on, and not realize it- until she looked at the DIC that has a light for it.

The fun is when you do your own pcm tune- you can change the performance shift tables to be significantly more radical if you'd like.

Honestly, something is wrong with that SRT or the driver if you're keeping up with a 3400 monte. Realistically, even the GTP should get whacked on by the SRT as well-especially with a stock pulley. That is assuming the driver can launch (they're really a pain with the small tires)- and shift.

 

Okay, its a done deal. Test drove it... whooooa!!! This thing is FAST!!! And this whole thing with the button for the different shifting, its got a tuned PCM so its got a big difference, well thats what he says. I wouldnt know cause I never drove it before the PCM tune. But I can say there is a huge difference in the shifting ( at least I think there is) Its got this spoiler Ive never seen on a GP though. He says its stock but I have never seen one like that before. Its kinda raised up in the back a little more than a regular one and, Im not sure how to explain it, its got dividers on it holding it to the back of the trunk?? Has anyone ever seen that. I really like the rims it has to, he says somthing about it having some "special edition" parts?? Roof rails, rims, and spoiler? Is this somthing that is more desirable in the "grand prix world"?
He has also done some custom modifications that include lowered seats, modified ram air, painted underneath the car, some interior painting, a scoop to throw more air into the engine bay, and LED's inside that go all around the top(almost look like it came from the factory) and thats about it. Ill get pics up as soon as I get a new camera or if I get mine fixed.

 

Roof rails are super popular- although I personally think they're ugly.

As for the bigger spoiler- as far as I remember, I think there are at least 2 spoilers that look like the regular GTP one- but are more raised in the back.

Definitely post up some pics- when are you planning to buy it?

 

Here in about 4-5 months. And I will get pics up as soon as I get my camera working or I get a new one.