trans question

[gectek]

ok so which table/cell do you modify for the WOT shifting on the PT. i have tried quite a few different ways and i still cannot get it to shift consistently at a single rpm from 1-2 or 2-3 shifting. itll usually go above 6800 revs before itll shift and even then itll stay at the 6800-7k mark for about 1-3 seconds before itll finally shift. i have the shift time set to .1 on all shift times, and i have changed them from .4 to .1 and the rpm from 6200 to 5200 and the mph as well and still no change in the shifting prob. any input?

[GA2000GTSpeed]

well when i changed myn i didnt change the shift time that much and i didnt change the mph that it shifts at... and i changed the rpm to 6000... and i also incressed the shift pressure by i think 15%. and i have myrev limiter for when im driving to 6400 i think. i think my prob the first time when i was tunning i had the mph shift points changed as well and i was having the same problems as u.

[silvergtjrad]

You have to modify the tables in the "shift point-Normal" section. We dont have a perf. shift button like the GTPs do.

[gectek]

unless you add a button of course...but i havent, i just copied and pasted the info from the perf cells to the normal, but it didnt seem to do anything really...maybe ill just look at smoothing the shift pressure and such and keep the times to .1 ms...maybe shorter if itll affect anything

[GA2000GTSpeed]

yah when i did myn i just did it to the normal and hot tables. i didnt mess with the urban,cruising,or performance. im just now learning how to really tune, but ive got the higher shift points at 6000 rpm down. ive just had to go through alot of trial and error.

[Shock24Z]

On the topic of WOT shifting... Has anyone else had any trouble in obtaining a crisp 1-2 shift? I know it was discussed in a thread on the PT boards awhile back but the thread never really pointed to any definite solution. I've played with most of the tables in the trans folder minus a few TQ management ones... I'm a bit leery of just wiping out TQ reduction at the shifts even though it could solve the lazy shift issue.

[lone_wolf025]

Ask Mark from MP Racing. I've had his tune on my car for sometime and under power that 1-2 shift was pretty nice.

[Shock24Z]

Ask Mark from MP Racing. I've had his tune on my car for sometime and under power that 1-2 shift was pretty nice.


That would be somewhat awkward. His knowledge of tuning earns his paycheck. If I just ask him to tell me how he does it its like asking him for free tools. If he wants to share some info in this thread he is welcome to but I couldn't ever expect that from a vendor.

[GT-squared]

I played around with mine last year for WOT shifting. I couldn't get a consistent shift either.
According to my tranny guy, the problem is line pressure. I had mine bumped up pretty high. The combination of higher RPM and higher line pressure is too much for the clutches. They can not release enough to allow the shift. I ended having to back off the throttle a bit at my shift point to allow it to upshift. If not, it would "hang up" there for a second or 2, stuck at high rpm. In the end, I brought both my line pressure down a bit and RPM down closer to stock, and seemed to work for me.

[AaronGTR]

I've noticed my shifts seem to hang sometimes too, even with the beefed up tranny. I haven't had time to play with the settings more, but I plan on seeing if I can't make it better. I was toying with the idea of dropping the redline down a bit too, as the trans doesn't seem to like shifting that high. GM only rated it for a max shift rpm of 6500 after all and my redline is 6300. Secondary reason I was thinking of dropping it is so I can run a smaller pulley on the SC without over spinning it. It will make more boost at lower rpm then and not peak too high at redline, so I think that may actually make it faster at the track shifting at a lower rpm.

[gectek]

well in my defense, i am running a 3.91 gear, but for some reason i was putting the shift rpm at 5900 even and it was still shifting at 6800 so idk what the deal was

[Shock24Z]

I've noticed my shifts seem to hang sometimes too, even with the beefed up tranny. I haven't had time to play with the settings more, but I plan on seeing if I can't make it better. I was toying with the idea of dropping the redline down a bit too, as the trans doesn't seem to like shifting that high. GM only rated it for a max shift rpm of 6500 after all and my redline is 6300. Secondary reason I was thinking of dropping it is so I can run a smaller pulley on the SC without over spinning it. It will make more boost at lower rpm then and not peak too high at redline, so I think that may actually make it faster at the track shifting at a lower rpm.

One bandaid fix I've found is to lower the shift rpm a bit. It firms up but obviously this is not entirely desirable.