Thread: Shift Quality
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Old Tue, December 29th, 2009, 07:00 PM
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The easiest way to get a more firm but yet comfortable shift is to change the target slip time by reducing the values (it's time) by about .25-1 ms. The TV pressure is a baseline that gives the shifts a "head start" so to speak in the adaptive strategy. The PCM can compensate up to about 20 PSI in most cases to achieve the desired slip time. That's the easiest way.

Bill and I have differing thoughts on the torque reduction during the shifts. I won't get in on his side of the coin, but I prefer to use the stock reduction or even a little lower values in the low APP ranges simply because I think it's better for the transmission. Bill doesn't believe that's true and it may not be but he can explain to you his thinking on the deal and you can make a choice for yourself.


Negative effects? I can't give you any as a slightly quicker shift is always better for the friction elements inside the transmission. A "mule kick" in the seat during a shift is obviously not good. As long as you can get a quick shift, minimize burn time, and keep it comfortable, it's a good shift.

I can show you a couple of my shift parameters if you'd like to try them.
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