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Transmission -> Shift Firmness

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Old Oct 26, 2004 | 10:04 AM
  #1  
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Default Transmission -> Shift Firmness

Can some explain the Negitive Pressure vs Temp table? I am guess that it is like the Positive Pressure vs Temp table, but is used on down shifts.

Base Pressure vs Torque and Brake Pressure vs Torque, what are these tables trying to do?

Keith
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Old Oct 26, 2004 | 12:43 PM
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I don't know about the Negative force motor table. I have
reprofiled the Positive to five me more (earlier) part-throttle
pressure so my TCC has something to work with, etc.

Base shift pressure vs torque goes to shift firmness.
You can change this profile to (say) give soft shifting
at low torque / throttle but come on hard when you
floor it, etc. (nice for the fussy girlfriend problem).

Brake pressure I believe is used on trucks, for engine
braking; on my car it is all zeroed. If you don't want
the tranny to freewheel when you're on the brakes
then you might play with something derived from a truck
tune.
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Old Oct 26, 2004 | 01:29 PM
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Originally Posted by jimmyblue
Brake pressure I believe is used on trucks, for engine
braking; on my car it is all zeroed. If you don't want
the tranny to freewheel when you're on the brakes
then you might play with something derived from a truck
tune.
Hmmmmm...... my stock Brake Pressure vs Torque on my C5 is as follows:

0 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150 160 170 180 190 200 210 220 230 240 250 260 270 280 290 300 310 320
Brake Pressure 2 0 0 0 0 0 0 0 3 7 10 13 16 20 23 26 29 33 36 39 43 46 49 52 56 59 62 65 69 72 75 78 82 85
Brake Pressure 3 0 0 0 0 0 3 6 10 13 16 19 23 26 29 32 35 39 42 45 48 51 55 58 61 64 68 71 74 77 80 84 87 90
Brake Pressure 4 0 3 6 8 11 14 17 20 23 25 28 31 34 37 39 42 45 48 51 53 56 59 62 65 68 70 73 76 79 82 84 87 90
So that means that the transmission is doing something to reduce the amount of torque defined in each cell?

Keith
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Old Oct 26, 2004 | 02:10 PM
  #4  
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Maybe 'vettes are set up for a little engine braking
(sports car drivers' preference?).
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