Tcc ramp rate by torque needs adjustment. Go higher than 800
Tcc ramp rate by torque needs adjustment. Go higher than 800
Does anyone else think this table (D5072) even works? At least on the 5speeds. I tried going both ways with no difference set all the way to zero or 1 and max it all out and this changes nothing. Logically the controller should adjust to match the ramp rate in D5072 so there would be no need to adjust it from stock, unless you want an annoying jerk when it locks up. But with a triple disk I guess your at the limits of the control logic, whats weird is you can watch DC and it will ramp quickly up to about 30-40% for a couple seconds with no decrease in in slip speed. Then all of the sudden it DC jumps all the way up and it locks hard.
Messing with the max and min DC tables you can drop the maximum to a certain point about 30% or something like that and you will get a few normal lockups, then eventually it will set a code and start halfway lockup and relocking. Moving the max duty cycle up just slightly it goes back to normal hard lockup that's really annoying. So theres definitely no linear correlation between duty cycle and tcc clutch pressure.
So is there any alternate strategy to attack this? Im assuming this will be the last revision of the TCM, but it seems like there maybe could be a workaround of trick?
Believe new table will help in preventing TCC from trying to lock. Useful in keeping TCC from overheating. Believe that after enough slip, slip is enabled.
Just started trying new ideas but seems that really strong TCC lock after 600 rpm slip is going to be difficult to program.
You have it backwards. The slip limit is a delta between input and turbine speed, yes. But not as an enable. It's a disable feature that when the slip threshold is above 600 RPM it inhibits TCC apply. This is to prevent excessive wear to the lockup clutch friction material and eventual TCC failure. Since most people switch to a triple disc TC when they add hp this feature isn't as necessary. Raising the slip delta to 1000 RPM or even higher allows the TCM to apply the TCC with no regard for the actual clutch friction material or heat generated by applying it with a large delta rpm.
You are correct, I did not state it correctly. Wish I would have re-read it! Thanks for pointing it out. If anyone could explain it best, that would be you. Thanks for the clarification that the TCM actually "disables" the TCC's ability to lock above 600 rpm of T/C slip.
With that, the whole premise behind this new EFILive feature is that you can now keep the TCC from inhibiting lockup at and above 600 rpm of slip, but at say 800 rpm of slip instead. It is like dumping a manual clutch at 800 rpm (or higher) of engine speed. But, as Brayden explains above, the parameter is there for your protection. I would not mod these tables unless you have the obvious upgrades.
2006 Ford F250 Super Duty, 2008 Cummins 6.7, Allison 1000 5spd
2011 Ford F250 Super Duty, 6.7L Scorpion
Is there enough tables available (Min/Max Duty Cycle and TCC Ramp Rate) to successfully make a suncoast triple disk converter to lock up as smooth as a stock converter or at least somewhat reasonably? The control logic makes no sense if you lower the max DC; the TCC will command on and it instantly ramps up to the max value and delta RPM does not change at all until about 2 seconds later then magically delta RPM goes to zero. If the max DC is below about 65% or so, for the majority of TPS values <75%TPS, It will lockup at part throttle about like stock. But If the converter is locked and you push the throttle without unlocking once the turbo starts to spool it will start slipping. So if you raise the Max DC at higher throttle positions it will make it lockup hard again even at low throttle positions.
Is the controller just at its limits since there is so much apply area with a triple disk? or is there a way to trick it at least with the tables we have available in the AL5? You would think that you could just leave the tables alone and maybe lower the MIN DC and the controller could adapt, and no adjustment would be required with the ramp rate since you want it to lock like stock, but I guess DC and lockup pressure have some weird non linear correlation.
this is awesome. My buddy is out testing our tuning on his truck; moving the slip RPM up incrementally to get a feel for it. He's gone from feeling locked in 4th (stock) to the top of third (800rpm) and now all the way through third (1500rpm). No reports of drive problems or odd shifting. It's a 2wd LMM with a Big Dipper Stage IV. Next we plan on logging some runs
Wally
2008 LMM
Just realized that has to be a kpa value, the table only goes to 146ish psi. I just tried setting the 400 and 600 ft-lb column to 900 kpa from 50-600 RPM, still not getting lockup until the 2-3 shift. Slip RPM right after the 1-2 shift is only around 330 RPM, and calculated torque is 487 ft-lb.
I am getting a weird thing where it looks like the TCC duty cycle increases, goes back to zero, and increases slowly again during 2nd gear. This happened on both WOT pulls I just tried. Any ideas what's going on?
Diff ratio is 3.42 and tire dia is smaller than stock, 30.75", not sure if that would throw anything off.
Last edited by thunder550; September 14th, 2014 at 09:51 AM.