Shifting Target

Shifting Target

Shifting Target Table

This sets the target Line Pressure when the Transmission Control function is shifting between gears.



If there is a base map available for your transmission, it is recommended to import the Target Pressure tables from there. 
If the transmission you're using has been rebuilt with upgraded components, ask your transmission builder what changes you should make to your target line pressures. 
If there isn't a base map available, the best thing to do is copy information from an already tuned vehicle using the same transmission. You may be able to find some information from OEM service manuals as to what pressures are used.
If you don't have access to any sources of information, you can use base maps for other transmissions as a starting point. This approach can cause problems, such as excessive wear and/or harsh shifts, but it's better than guessing. 

General Guidelines

  1. If possible, start with the most relevant base map.
  2. Start with a higher line pressure and work backwards until the shifts feel less harsh.
  3. If you get slippage in the transmission while in gear, increase line pressure. 
  4. More engine torque requires more line pressure. 
  5. In most transmissions, more line pressure results in quicker shifts, which can increase harshness. However, if the line pressure is too low, then the shift can also feel harsh. 
  6. If the shift doesn't complete well enough within the time allocated in the Shift Duration table, either increase Shifting line pressure, or increase the Shift Duration.
    This can be determined by looking at a trace of the Engine RPM, observing when it gets brought down by an up-shift. Compare this to the Transmission Control State, Transmission Control State Time and Transmission Control Shift Progress channels. If the Shift progress reaches 100% and the state changes before the Engine RPM has finished moving, then the shift is taking longer than the Shift Duration table value. So the Shift Duration and/or Line Pressure Shifting Target should be increased until the shift completes in time. It is OK if the Shift Duration table is higher than ideal. The only down-side will be that the next shift can't start until after the current shift is considered complete and the ECU waits for the Post Shift Lock-Out. 
  7. If there isn't a relevant base map, start with very high line pressures, and gradually decrease them until the shift quality starts getting worse or the engine flares (RPM increases when it shouldn't), then bring the line pressure back up to a good amount. 

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