WOT Shift Question
07-03-2004, 11:36 PM
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WOT Shift Question I have my shift points set at 6000/6000/6000 and 38/72/117mph accordingly under WOT. Now when I go to WOT it shifts at 5600-5700, which is approx 38MPH. Why wont it hold on to 6000RPM?
Even if I hold it in 1st, it still shifts at 5700RPM. Is there bugger all slip in the converter for 1st gear at WOT or is there something else triggering the early shift?
2nd-3rd shifts at WOT aropund 6100RPM. As a rule of thumb, how do you configure your WOT shifts?
Even if I hold it in 1st, it still shifts at 5700RPM. Is there bugger all slip in the converter for 1st gear at WOT or is there something else triggering the early shift?
2nd-3rd shifts at WOT aropund 6100RPM. As a rule of thumb, how do you configure your WOT shifts?
07-04-2004, 08:15 AM
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are you sure your engine isn't just outrunning your tach needle? you might actually be turning 6k when it shifts. I had to raise my shift points with hpp3, even though I specified 6200 rpm shift points when I sent out my pcm to be tuned, it was shifting at 5500 or so. I set my 1-2 at plus 3 mph and my 2-3 at +7 mph
07-04-2004, 08:33 AM
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How can you check that? Does the ECM use a different sensor to the RPM needle? Would a scan show it up?
Ive since used the Search button and found a lot of useful information regarding shift points, however, no real data on how the ECM interprets the WOT RPM/MPH values. Some ppl. say it shifts vs. MPH, as per the 0-100% TPS tables and that the RPM limits are a flag or something. Others say both RPM and MPH must be met before a shift.
Does anyone know the answer?
I put it into 1st gear and held onto it under a WOT run and it shifted at 5500rpm and 38MPH. I have my MPH shift set at 38 and 6000RPM. How come it wont hold on till 6000? I probably have my answer in that MPH is the shift determinator, so what use is the RPM?
Ive since used the Search button and found a lot of useful information regarding shift points, however, no real data on how the ECM interprets the WOT RPM/MPH values. Some ppl. say it shifts vs. MPH, as per the 0-100% TPS tables and that the RPM limits are a flag or something. Others say both RPM and MPH must be met before a shift.
Does anyone know the answer?
I put it into 1st gear and held onto it under a WOT run and it shifted at 5500rpm and 38MPH. I have my MPH shift set at 38 and 6000RPM. How come it wont hold on till 6000? I probably have my answer in that MPH is the shift determinator, so what use is the RPM?
07-04-2004, 10:29 AM
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Earlier LS1s shift on MPH alone. Later LS1s shift on BOTH MPH and RPM. Both programmed parameters have to be met for the shift to happen.
What year is your car?
The tachs are slow and this is much more noticable in 1st where the RPMs are climbing quicker. It uses the same VSS (vehicle speed sensor) as the PCM but just physically moves too slow. It gets the right reading, it just can't keep up.
What year is your car?
The tachs are slow and this is much more noticable in 1st where the RPMs are climbing quicker. It uses the same VSS (vehicle speed sensor) as the PCM but just physically moves too slow. It gets the right reading, it just can't keep up.
07-04-2004, 10:34 AM
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Originally Posted by Colonel
Earlier LS1s shift on MPH alone. Later LS1s shift on BOTH MPH and RPM. Both programmed parameters have to be met for the shift to happen.
What year is your car?
The tachs are slow and this is much more noticable in 1st where the RPMs are climbing quicker. It uses the same VSS (vehicle speed sensor) as the PCM but just physically moves too slow. It gets the right reading, it just can't keep up.
What year is your car?
The tachs are slow and this is much more noticable in 1st where the RPMs are climbing quicker. It uses the same VSS (vehicle speed sensor) as the PCM but just physically moves too slow. It gets the right reading, it just can't keep up.
My car is a current series Holden Monaro. Its the American equivalent of the GTO. Its current, only 5 months old. Could there be something else causing the short shift? I will just raise the shift MPH anyway, but it concerns me I may be masking a problem.
07-04-2004, 10:38 AM
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Try this, lower the WOT shift MPHs to a low number like 5 MPH. Then set your WOT shift RPMs to whatever you want them to be. If it's like a late model F-body or C5 then it will shift based solely off of RPM if you do this.
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07-05-2004, 05:27 PM
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have my shift points set at 6000/6000/6000 and 38/72/117mph accordingly under WOT. Now when I go to WOT it shifts at 5600-5700, which is approx 38MPH. Why wont it hold on to 6000RPM?
As you have yours set up, if your are cruising along on the interstate at 75MPH then you would be in 3rd gear, making your RPM's somewhere around 3000 - 3500. Whereas if the shift points were at stock, the RPM at 75 MPH would be somewhere around 1700 and then tranny would be in 4th.
Correct me if I am wrong, but wouldnt this have a seemingly diverse affect on MPG?
Please dont get me wrong, I would love to liven up my A4, but I do a lot of interstate driving
and I dont want to spend all of my MOD money on Gas! 
Any suggestions that anyone has are appreciated...
RICE
07-06-2004, 04:30 AM
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This Thursdya I will be scanning with EFILive exactly what is going on and then post my resolution. BTW, is it safe to wind a stock LS1 up to 6400/6500rpm with only replacement dual valve springs?
07-06-2004, 10:56 PM
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I've wound mine that high with stock valvesprings, my rev limiter is set at 6600 and I've bounced off of it during transmission failure many times, along with the occasional misjudgement of speed when doing a manual downshift. I shift at 6200 1-2 and 6400 2-3. I've tried higher shift points before the blower but it felt like it wasn't pulling any more if I wound it higher, so I set them back down.
07-07-2004, 03:47 AM
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1-2 shift
Originally Posted by MNR-0
This Thursdya I will be scanning with EFILive exactly what is going on and then post my resolution. BTW, is it safe to wind a stock LS1 up to 6400/6500rpm with only replacement dual valve springs?
LOWER mph and raise RPM up in the 1-2 shift whatever you dare
the 2-3 shift is right on
07-08-2004, 06:05 AM
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An update on my post. Went to my Tuner to scan the shifts recording TPS, MPH and RPM only to find I couldnt find 2nd gear anymore! 
The Transmission is only 4 months old and I paid to have it rebuilt and shift kitted to avoid exactly this kind of thing!
I took it to the dealer and we scanned it using Tech-2 and wouldnt you know it, floor it from a rolling start in 1st and it falres up to redline. Looks like I have a slipping clutch and a burnt tranny.
So, perhaps a failing tranny caused all those weird shifts.
Im planning on getting it rebuilt tomorrow and in the afternoon revisiting the shifts. With luck I can still make it to Calder for a run. This explains so much...
Will keep you all posted until I have my shifts (and tranny) sorted.
The Transmission is only 4 months old and I paid to have it rebuilt and shift kitted to avoid exactly this kind of thing!
I took it to the dealer and we scanned it using Tech-2 and wouldnt you know it, floor it from a rolling start in 1st and it falres up to redline. Looks like I have a slipping clutch and a burnt tranny.
So, perhaps a failing tranny caused all those weird shifts.Im planning on getting it rebuilt tomorrow and in the afternoon revisiting the shifts. With luck I can still make it to Calder for a run. This explains so much...
Will keep you all posted until I have my shifts (and tranny) sorted.
07-08-2004, 06:06 AM
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Originally Posted by MNR-0
An update on my post. Went to my Tuner to scan the shifts recording TPS, MPH and RPM only to find I couldnt find 2nd gear anymore!
The Transmission is only 4 months old and I paid to have it rebuilt and shift kitted to avoid exactly this kind of thing!
I took it to the dealer and we scanned it using Tech-2 and wouldnt you know it, floor it from a rolling start in 1st and it falres up to redline. Looks like I have a slipping clutch and a burnt tranny. So, perhaps a failing tranny caused all those weird shifts.
Im planning on getting it rebuilt tomorrow and in the afternoon revisiting the shifts. With luck I can still make it to Calder for a run. This explains so much...
Will keep you all posted until I have my shifts (and tranny) sorted.
The Transmission is only 4 months old and I paid to have it rebuilt and shift kitted to avoid exactly this kind of thing!
I took it to the dealer and we scanned it using Tech-2 and wouldnt you know it, floor it from a rolling start in 1st and it falres up to redline. Looks like I have a slipping clutch and a burnt tranny.
So, perhaps a failing tranny caused all those weird shifts.Im planning on getting it rebuilt tomorrow and in the afternoon revisiting the shifts. With luck I can still make it to Calder for a run. This explains so much...
Will keep you all posted until I have my shifts (and tranny) sorted.
