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Upshifting/Downshifting

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Old Oct 28, 2004 | 12:21 PM
  #1  
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Default Upshifting/Downshifting

My car upshifts way too early and won't downshift. What could be the problem? I have a Predator. Can't get anyone to tell me what the mph shift points should be. I have 373 gears?
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Old Oct 28, 2004 | 02:40 PM
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The 3.73 setting for proper speedo has to be done first.
There's something not quite right about that, with the
Predator, but there is a special workaround that you can
follow. I think I even read it in the little book that came
with mine. Get that right, first.

MPH settings for 6000RPM upshift and 6250RPM limiter:

3.23: 40, 80, 125
3.42: 38, 76, 120
3.73: 35, 70, 110

These should be considered starting points, because
the torque converter, transmission shift cycle time
and engine output torque all change the MPH to RPM
relation of the shifts and limiters.

The Predator is a bit funny w/ the trans settings; it
changes up and downshift, including part throttle,
when you adjust the WOT shiftpoints. The higher
upshift, the better your downshift MPH too. Until
you start hitting the rev limiter.
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Old Oct 29, 2004 | 08:26 AM
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Thanks for the info. I've got a 373 trans so I'll put that into the Predator tonight.
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Old Oct 30, 2004 | 08:14 PM
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Originally Posted by Silver02
Thanks for the info. I've got a 373 trans so I'll put that into the Predator tonight.
The shift points are correct. It must be something else. This car upshifts way to early under part throttle and definately won't down shift.
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Old Oct 30, 2004 | 09:52 PM
  #5  
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Part throttle shifts should be controlled purely by MPH
and TPS. Did you get the speedo settings proper? That
is fundamental.
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Old Jul 27, 2006 | 03:22 PM
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My car is experiencing the same problem but it is intermitent. Its a 98z and had a tuner redoe shift points. Before, it did it all the time, no it does it part of the time. Checked the tps while tuning it and it was reading good. Could it be solenoids or maf?
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Old Jul 29, 2006 | 07:25 PM
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ttt...
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Old Aug 15, 2008 | 03:58 AM
  #8  
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Sorry to bump this thread but can anybody post the workaround out of the instruction book please? I lost mine and can't find it anywhere on the net
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