Black LS1 T/A

"We recommend the Diablo Sport Predator (#20X) be used on all 1998 up 4L60E performance transmissions for the following reason. All 1998 ups have a Torque Management System that picks up the higher stall speed and firmer shifts. When this happens the computer thinks there's a problem and turns the pressure down. Then it detects a slip and turns the pressure up too high and blows the end out of the clutch drum. This problem is corrected with the use of the Predator. The price doesn't include Camaro type 6 bolt tail housings or C4 Corvette tail housings."

This is from Raptor Transmission site.

If this is true, how do we resolve this with tuning?

Thanks!

Stone0fFire

i dont think this is true.

i added a 4000 stall and nothing bad happened.
i added a shift kit set up for "HIGH STALL RACE ONLY" and nothing bad happened.

i guess they want you to buy that thing and use it to disable torque management.

let someone else explain what torque management really does.
i dont know the details.

calongo_SS

iTrader: (7)

As far as I know all torque managment does is pick up added slip of the converter. When it does it pulls lots of timing. It makes a huge difference when shifting. The car will fall on it's face. FWIW, I've had my tuner turn TM way down, and never thought about it again. To my knoledge TM is really only a problem in 01 & 02 cars.

moeZ28

iTrader: (7)

torque management affects 98 cars for sure. mine used to pull a ton of timing till i had it turned as far down as possible.

wait4me

iTrader: (10)

The problem with slipping clutches from a transmission with a shift kit such as the Raptor contains, is caused from the Shift adaptive learning system. not Tm....

If the trans kit is shifting at say .100 of a second, and the transmission is being commanded to have a .560 of a second shift, The computer then tries to slow down the shift to get to the commanded shift time.. That is where the problems occur....

wait4me

iTrader: (10)

Tm does not pull line pressure..

Line pressure durring shifts is however effected by the pcms calculated torque. So, i guess Technically, if the pcm pulls lots of timing it "could" effect the shift pressure, BUT it all happens to quickly for it to even be able to effect line pressure.

Black LS1 T/A

I just thought I'd ask because I have been having a problem where my tranny won't shift at the speed/rpm threshold set when I am at WOT and have traction... it shifts way early and I get "transmission component slipping" errors, then my tranny will fail.

I can vouch for the TM thing... until I removed TM, shifting was like nose-diving a granny shift with a manual. I may have to add some TM back or just flat-out reduce my torque in that RPM range to be able to keep a 4L6E in there...

ToplessTexan

Michael, my first concern would be whether or not your MAF cal was accurate (since delivered torque values will be derived from that input in conjunction with others), but maybe that's just my knee-jerk response. I'd have thought you'd have gone to a vaccuum modulated setup long ago... Have you been monitoring any tranny parameters, e.g. desired and actual force motor current? Would be useful to know 1) that it's doing what you asked it to do and 2) that you've asked it to do the right thing. Some additional scanning might be helpful. Beyond the more obvious tranny related PIDs, take a look at the TSTATExx PIDs. There's a lot of info there.

Are you really seeing P1870 or P1860 errors? You should only see these set under TCC lock up conditions, a little different animal from WOT.

Brains

iTrader: (7)

Jesse nailed it above. One thing you should do when you put in a built transmission with "sticky" frictions, is log the shift time pids. Clear the PCM to reset the adaptive shifts, and go for a drive. Set your desired shift time a tiny bit faster than the transmission is actually shifting and it'll minimize slippage. If you have a higher stall speed converter, the harder/quicker shifts won't be felt as much anyway, and your trans will live longer.

If you have stock frictions, they can deal with the heat *much* better than the aftermarket types (ie. blue plate specials, red eagle, etc.). In those cases, you can typically leave the desired shift times alone without problems. At WOT, the PCM will command an immediate shift (ie. max line pressure according to the table) anyway.

ToplessTexan

wait4me and brains, are you saying that {D1108,9,10} (target shift durations) apply at WOT as well? I guess I was under the impression that the adaptation cells were not used at WOT (similar to LTFT trimming.) If {D1108,9,10} are applicable at WOT, it would seem they are.

Black LS1 T/A

This is the run:

http://www.blackls1ta.com/ShortShift.xls

I ran almost the whole track in 3rd gear and made a 10.84 at 125 MPH.

This is the data I have for that run.