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Evening guys,

I have a couple qeustions regarding what a couple trans related tables are and if they referance one before another.

Background: Vt v8 running a 4l60e on $A6C,trans is shift kitted with a HD2 kit. 3000 high stall.

Couple tables regarding 2-3-4 pressure offset, There are two tables titled normal and performance which i understand but there is also one that is labeled 2-3-4 pressure offset vs TPS
1. Is the 2-3-4 pressure offset vs TPS table a Global PSI table? then the NORMAL or PERFORMANCE tables add or subtract off that table? Obviously they are all offsets of the main force motor table?
Also are they tables for just the pressure for the shift or the pressure added to what ever the force motor table says for that TPS and VSS?

2. The pressure ramp delay table? what is it? ive commanded a target shift time of 0.40 through 1-2 and 2-3 and 2.0s for 3-4 but i only really achieve a shift time of mid 0.60-0.70 for 1-2 and 2-3. Is this becasue the pressure ramp is delayed 0.30s for those shifts?

Thanks, i dont want to torch this trans as quick as the original.

yes global modifier table per gear.

Pressure ramp delay tables i need to fix up, this is the switching delay time before pressure ramps for a shift, there is two pressure adder tables, i havn't added them yet, nothing to exciting, if you want to spice the shifts up a little mainly adjust the main pressure table and shift pressure adder scalars.

For tuning watch your force motor current and slip rpm, if your shifts are between 0.30 - 1.00 then it's normal, if sliprpm is over 1000rpm while not shifting then either you dont have enough pressure or something is worn or slipping.

The1 wrote:yes global modifier table per gear.

Pressure ramp delay tables i need to fix up, this is the switching delay time before pressure ramps for a shift, there is two pressure adder tables, i havn't added them yet, nothing to exciting, if you want to spice the shifts up a little mainly adjust the main pressure table and shift pressure adder scalars.

For tuning watch your force motor current and slip rpm, if your shifts are between 0.30 - 1.00 then it's normal, if sliprpm is over 1000rpm while not shifting then either you dont have enough pressure or something is worn or slipping.

Ok thanks. Is there any gain in zeroing out the ramp rates in 2 and 3 like 4th is? My target shift time is set at .40 and ramp rates .30. I'm thinking this is the reason why most of my shifts are near the .70 range?

I thin I had the line pressure up to high in the last tune as it was doing .10 and .20 shifts which would explain why the band went from overlap.

yes you dont want any quicker than 0.30 otherwise overlap issues will occur, if your getting down that quick you must have a built box. Zero'ing ramp rates prob wont achieve anything, very little difference in factory tables.

Ok i zeroed ramp rates and no change. This screen shot is what im worried about... PSI isnt that high but its changing into 3rd in 0.05 seconds occasionally. Other times its around 0.70 seconds except for these strange occasions.. Box isnt built just shift kitted
Any ideas?

can display gear ratio on that, will give a better indication of shift time.

Will the gear ratio show why it's so quick?

The torque converter feedback flag seems to flick on and off in the logs aswell? If that may have something to do with it. I may pull some 2-3 gear change pressure out and see if that lengthens the time. Seems only to do it at low tps. Main line pressures down in that region are like 2psi but the 1-2 2-3 and 3-4 up shift pressures are at 7psi so will drop them.