jeremy Posted April 13, 2008 Report Posted April 13, 2008 What does this actually do? Does it actually help lower 1/4 mile times? or is it just another Pontiac "gimmick" '99 GTP. Thanks!
89GranSport Posted April 13, 2008 Report Posted April 13, 2008 Q: I have a GTP and it has a selection for "Performance Shift." What does it do, and in what driving situations would I want to use it? A: Putting your GTP into "Performance Shift" mode raises the RPM level at which the transmission shifts into the next highest gear, and may allow your RPMs to go a bit higher than in normal mode. Use it for getting up to speed more quickly, passing (except when in 4th gear; it won't help here), racing, etc. According to those more sensitive to the shift characteristics, "Performance Shift" mode feels quite a bit more firm and quick during shifts than normal mode. http://www.grandprix.net/faq/ My mom has a Bonneville SSEI that also has the performance shift button, you can definitely feel a difference between the normal shift mode and the performance shift mode. However, I have no idea if it would improve your 1/4 mile time, if it did, I imagine it wouldn't be much.
1990lumina Posted April 13, 2008 Report Posted April 13, 2008 I think it might also increase the pressure in the tranny to hold the gear better and have firmer shifts too
5speedz34 Posted April 13, 2008 Report Posted April 13, 2008 I think it might also increase the pressure in the tranny to hold the gear better and have firmer shifts too Yup. I think if you have it on all the time it will cause more wear on the transmission. And it reduces fuel mileage. For someone who calls out people for stupid posts, this could've easily been found by searching clubgp.
jeremy Posted April 13, 2008 Author Report Posted April 13, 2008 For someone who calls out people for stupid posts, this could've easily been found by searching clubgp. the search feature on clubgp vary rarely works properly for me over there and I figured if I was going to post a new thread I would post it over here
digitaloutsider Posted April 13, 2008 Report Posted April 13, 2008 I think it might also increase the pressure in the tranny to hold the gear better and have firmer shifts too Yup. I think if you have it on all the time it will cause more wear on the transmission. And it reduces fuel mileage. For transmission wear, it does the opposite. 4T65E's like to slacken up in the shift department as they age. Slow, sloppy shifts mean increased clutch wear, less accurate shifts and more overall "abuse". The performance shift tables in the PCM are definitely different from the non-PS tables and include quicker shift times, max shift pressure at lower RPMs and slightly raised shift points. It does make a difference. As far as gas milage, I can't imagine the average 500 RPM higher that PS makes it shift at makes any real difference.
IRONDOG442 Posted April 13, 2008 Report Posted April 13, 2008 I think it might also increase the pressure in the tranny to hold the gear better and have firmer shifts too Yup. I think if you have it on all the time it will cause more wear on the transmission. And it reduces fuel mileage. For transmission wear, it does the opposite. 4T65E's like to slacken up in the shift department as they age. Slow, sloppy shifts mean increased clutch wear, less accurate shifts and more overall "abuse". The performance shift tables in the PCM are definitely different from the non-PS tables and include quicker shift times, max shift pressure at lower RPMs and slightly raised shift points. It does make a difference. As far as gas milage, I can't imagine the average 500 RPM higher that PS makes it shift at makes any real difference. Shaun exactly what I thought.
slick Posted April 13, 2008 Report Posted April 13, 2008 Actually... 500 rpm does make quite a difference. Doing a test, just recently on the highway, I averaged about 6 mpg better dropping my RPM by 500.
digitaloutsider Posted April 13, 2008 Report Posted April 13, 2008 Well yes, 500 RPM consistently, but just the extra 500 RPM during shifts?
5speedz34 Posted April 13, 2008 Report Posted April 13, 2008 For someone who calls out people for stupid posts, this could've easily been found by searching clubgp. the search feature on clubgp vary rarely works properly for me over there and I figured if I was going to post a new thread I would post it over here Ya, it really does suck. Not try do dog you but, you could've tried MIGPC's site. As for transmission wear thats good to know. I'm just basing off what my friend told me. He doesn't keep performance shift on because of the MPG. I can see it going both ways, someone needs to do a test.
jeremy Posted April 13, 2008 Author Report Posted April 13, 2008 Not try do dog you but, you could've tried MIGPC's site. haven't been posting on that site much lately since the whole MiGPC member got in a huge wreck going 100mph street racing mess....I was all excited about attending a lot of their event's this year but now I am not so sure... ...and fwiw: it's not like that question doesn't pertain to this forum, it is a w-body
digitaloutsider Posted April 13, 2008 Report Posted April 13, 2008 As for transmission wear thats good to know. I'm just basing off what my friend told me. He doesn't keep performance shift on because of the MPG. I can see it going both ways, someone needs to do a test. Your friend likely doesn't know what he's talking about.
GP1138 Posted April 13, 2008 Report Posted April 13, 2008 haven't been posting on that site much lately since the whole MiGPC member got in a huge wreck going 100mph street racing mess....I Link? Details? I'm bored.
5speedz34 Posted April 13, 2008 Report Posted April 13, 2008 Not try do dog you but, you could've tried MIGPC's site. haven't been posting on that site much lately since the whole MiGPC member got in a huge wreck going 100mph street racing mess....I was all excited about attending a lot of their event's this year but now I am not so sure... ...and fwiw: it's not like that question doesn't pertain to this forum, it is a w-body I know its just kind've a total noob question. I'm just giving you shit. My buddy was pissed at MIGPC's stance on the whole thing. They are all west siders on that board. It's a different mentality over there. haven't been posting on that site much lately since the whole MiGPC member got in a huge wreck going 100mph street racing mess....I Link? Details? I'm bored. Just look on ClubGP in the general section its there. MIGPC won't allow any threads on it.
BIGBULS Posted April 14, 2008 Report Posted April 14, 2008 BTW. Shift *RPM* at WOT does NOT change from Normal shift mode to Performance. At PART throttle they change, but WOT, the only difference is a slight bump in pressure (so NOT a noticeable diff in 1/4 times). Your best bet for shift logic, is to launch and run the 1/4 in "2". This nets you the higher 5800rpm 1-2 shift, and allows you to hold 2nd through the traps with a shift into 3rd just past the 1000ft mark.
slick Posted April 14, 2008 Report Posted April 14, 2008 Well yes, 500 RPM consistently, but just the extra 500 RPM during shifts? Nah, during shifts, won't make enough of a difference to matter, especially if your going WOT anyways.
93CutlassSupreme Posted April 14, 2008 Report Posted April 14, 2008 http://www.clubgp.com/newforum/tm.asp?m=4350009&p=1&tmode=1&smode=1 I'm not surprised. I've always thought MiGPC was a smaller, local version of ClubGP and this proves it even more for me. I don't know who these two dumbass drivers are, but I hope that the administration of this forum (w-body.com) would have the decency to ban these individuals if they are members and/or prevent them from signing up here if they are not.
Euro Posted April 14, 2008 Report Posted April 14, 2008 http://www.clubgp.com/newforum/tm.asp?m=4350009&p=1&tmode=1&smode=1 I'm not surprised. I've always thought MiGPC was a smaller, local version of ClubGP and this proves it even more for me. In that thread there are a couple vids of guys doing burnouts on fairly populated roads. MIGPC aren't the brightest crayons in the box.....
93CutlassSupreme Posted April 14, 2008 Report Posted April 14, 2008 http://www.clubgp.com/newforum/tm.asp?m=4350009&p=1&tmode=1&smode=1 I'm not surprised. I've always thought MiGPC was a smaller, local version of ClubGP and this proves it even more for me. In that thread there are a couple vids of guys doing burnouts on fairly populated roads. MIGPC aren't the brightest crayons in the box..... I agree 100%. Arrogant trash that doesn't give a fuck about the lives or safety of anybody else.
5speedz34 Posted April 14, 2008 Report Posted April 14, 2008 Most of the MIGPC guys are pretty cool. I don't know why they did a burnout on a populated road. So all of a sudden we're supposed to ban someone for what they do in their free time? The kid is a idiot who was racing, but thats no reason for everyone to fucking come down on him. Seriously, "the person without sin should cast the first stone."
Euro Posted April 14, 2008 Report Posted April 14, 2008 I think he's just a dumbfuck for doing 100mph in a residential 45mph zone at 5pm rush hour...
slick Posted April 14, 2008 Report Posted April 14, 2008 Woah woah woah! Way off topic already. The question has been answered, no need to keep it open.
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