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Performance Shift Button

wstefan20

wstefan20

New member
I've searched every section of this forum and haven't found anything super clear regarding this, so sorry for the noob post.

I know it's possible and fairly simple and involves pin 23 on the PCM, but that's about it!
I know the computer needs to be re-programmed, but is this part of any zzp, intense, overkill, etc. pcm tune?
Or is this something I've got to jack Selliot's HP tuner for? (I really hope he sees this post :th_winking:)

Looks like there used to be a write-up, but the link is long broken. Anyone done this with success or know the working link to the how to?

Any advice is helpful!
 


If you already have a 2001-2003 without the button, adding it is not needed.

It will go into performance shift mode on it's own under full throttle. You are better off just tuning the transmission to make it shift how you want it all the time.
 
My main motivation is that I use this as my daily driver. I know different shift points will affect my mpg but also the performance. I'd like two shift tables for both options if possible. Would adjusting shift points give me better gas mileage? and at what point will it damage my transmission?

And if that's not possible, I'll get a wiper fluid pump and wire this switch to it and have a drink dispenser! lol so many options!!!
 
The difference is not even something you'd even notice. There is at most a 3-5mph difference in shift mph when under 50% throttle. It bumps up to a 4-6mph difference at 60-80% and 2nd gear has a 5-6mph higher shift point when in performance mode. Your vehicle will already enter the PS mode to shift at around 80mph for the 2-3 shift. I can't post tunes here and you'd need HP Tuners to see them. Screen shots are a hassle lol.

That in no way is going to change how much miles per gallon you are going to get. I had my car for nearly 5 years and it was tuned for almost 4 years. I kept it in performance shift mode like 100% of the time and it never changed my mpg even when I tried it without.

If you did tune it you could adjust the shift mph to your liking but I don't see how anyone is going to gain much from it. It'll just feel more lazy and shift too soon if someone where to lower the mph points too much during light throttle. Around town mpg is already horrible, I got 14-16 in the city as that's all I drove, maybe 18in the summer when it was nice and still got 30 on the freeway.

Tune the shift times and shift pressures to gain the desired results you wish.
 
Thanks for all the information! Now if I can just learn HP tuners.... lol

Wow! I should thank my lucky stars then! I'm averaging 20mpg around town and between 25-30 highway! (course I just rebuilt my engine to factory specs on all bearings and rebuilt my transmission so...) :th_laugh-lol3:

I'm sure I can come up with something cool to do with the shift button then!

If anyone has any suggestions feel free to chime in!
 
Yeah that's pretty decent mileage. I used dhp to tune my gtp, and was able to get an additional 2 - 3 mpg on the highway by adding a bunch of timing in the cruise tables, but I don't think my city mileage changed much. I think that's about the best you can hope for.
 


I put one of them shift knobs in my GP years ago. The plan is/was to hook it up to some lights or something cool. For now, I just click it in and off while I drive; might wear it out before I get around to hooking it up. LOL

Shift_Knob_019.JPG
 
After 2001 performance shift was locked in the PCM even if it was unlocked the tables were the same. It was just a light that came on. I bought the last new performance shift shift knob GM had left. It’s pin 23 in the PCM bottom connector I believe. I had mine “custom” tuned so the shift pressures are noticeably different as well as shift points when you start digging into the throttle. I wanted the switch because it’s a daily driver and I’ve noticed when the transmission is cold it shifts pretty hard so I leave it on the stock tables until it warms up a bit. And it’s nice to have anyway if you just want to drive around on stock shift tables.


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GrandPrixGT1 said:
After 2001 performance shift was locked in the PCM even if it was unlocked the tables were the same. It was just a light that came on. I bought the last new performance shift shift knob GM had left. It’s pin 23 in the PCM bottom connector I believe. I had mine “custom” tuned so the shift pressures are noticeably different as well as shift points when you start digging into the throttle. I wanted the switch because it’s a daily driver and I’ve noticed when the transmission is cold it shifts pretty hard so I leave it on the stock tables until it warms up a bit. And it’s nice to have anyway if you just want to drive around on stock shift tables.


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Interesting. So you're saying that you noticed a difference and all you have to do is have the pcm tuned to "unblock" these tables? I do notice that the shift is pretty firm because of the transgo shift kit. What all was involved?
 
wstefan20 said:
Interesting. So you're saying that you noticed a difference and all you have to do is have the pcm tuned to "unblock" these tables? I do notice that the shift is pretty firm because of the transgo shift kit. What all was involved?
Click to expand...
Yes you'll need to get the PCM tuned. The transgo is a mechanical thing so you'll always feel that. Ground Pin 21 on the top connector I believe is where it is and wire that into the cabin with a switch to ground. Verify that your switch is working with a multimeter and then your good after you get it tuned. Im pretty sure its the top connector id have to look at mine to see where I have it.
 


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