It won't upshift!!!!

[Chevvy SS]

I recently changed the torque converter to a 2500-3000 stall, and the diff ratio from 3.07 to 3.46 on my 2005 Chevvy Lumina SS 5.7.

Rev limiter is set at 6500 and upshift rpm at 6300 on Power Mode in WOT, as before the mechanical changes. My tuner correctly put in the new values and it was saved and calculated before we loaded the new tune.

Now it hits the rev limiter, does not upshift, actually bounces to about 6700 rpm and only changes up when u lift your foot. This happens in the 2-3 and 3-4 upshift. I did not have the problem with the same upshift settings before changing the diff ratio and converter.

As I live some distance from my tuner, and his time is limited and this is rather frustrating, I would appreciate all the help I can get. Unfortunately, it is not possible to forward the tune.

Thanx guys.
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Easy vape

[ds8]

I think your WOT shift speed has to be change too. There are two conditions that have to be met at WOT...above some speed and above some RPM. Your gearing may not allow you to reach the speeds the old gearing did. With the old gearing you would have passed the speed requirement and then the RPM would control the shift. Now you pass the RPM requirment, but not the speed. Adjust the WOT shift at speed table and the tune should work properly. This table doesn't realize you changed gearing and has to be changed manually.

[Chevvy SS]

I think your WOT shift speed has to be change too. There are two conditions that have to be met at WOT...above some speed and above some RPM. Your gearing may not allow you to reach the speeds the old gearing did. With the old gearing you would have passed the speed requirement and then the RPM would control the shift. Now you pass the RPM requirment, but not the speed. Adjust the WOT shift at speed table and the tune should work properly. This table doesn't realize you changed gearing and has to be changed manually.

Thanx, but I think the speed is automatically calculated and reduced by +- 11% by the program itself when the ratios were changed. Will let u know, however.
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Pornstars hungarian

[ScarabEpic22]

I would try and lower the WOT shift MPH and WOT shift RPM. I had an issue with my TrailBlazer on the 1-2 shift where it would hold at ~6300rpm (shift was set at 6100rpm) for .2-.5sec until it banged into gear. Bad times, but my tune now shifts firmly at 5900rpm and at 40mph.

[Chevvy SS]

We went through the whole tune again, and the speeds for upchanging at WOT was reduced by the tune itself when we put in the new diff ratio. We decreased it by another 5%, upped the line pressure on the box, but the problem is still there.

I do not want to lower the shift rpms, as my motor is spinning freely there. Any other suggestions
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Cloudy trichomes

[joecar]

Try this:
Set the both MPH and RPM low enough that you get shifts;
then increment the RPM until it shifts at the desired RPM;
then increment the MPH until the shifts don't happen, and then back off by 10 mph.

[Chevvy SS]

Try this:
Set the both MPH and RPM low enough that you get shifts;
then increment the RPM until it shifts at the desired RPM;
then increment the MPH until the shifts don't happen, and then back off by 10 mph.

Thanx Joecar, I will def. try that out, but can't it be line pressure as well? And, can line pressure only be set through the PCM?
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Yamaha qt50 history

[zrx1200]

when setting the mph for the shift efi displays down the bottom of the page the rpm..remember though the tc is unlocked and they wont be acurate.i've been setting the shifts 10% lower seems to work..also lifted the rev limit to 6900..but im not using more than 6600.