6l80e with 3000rpm converter. wont stay locked. pulsing.

[parish8]

well I called it an early day due to a bad day. I did some datalogging on the way home, and the logs speak for themselves on the lockup. I did some light,moderate and hard throtle pulls.Now that I have the lock up part done, Im going to work on the drivability of the tune. Parish I appreciate the tune info, Ill look it over and see what works for me.Im pretty determined, so I know Ill get most of this, but help is always nice.
Heres some data logs from tonight. Mill st to H st is alllight andmoderate driving. The Hst to home was2hard runs and normal driving.The first wot pull ended when a car cutme off. The second wot pull ended when I saw the CHP on the side of the road..look at how fast I slowed down..Was kinda funny tho.
Ill be working on the shift feeland quality and post as I go. Adam

hmm, thats some good logs you have there. at first i was just seeing mph's near or over 70mph and thinking that didn't show much but that 2nd log has a long time at 50-60mph and other than one little bump it looks to be locked pretty solid.

i would love to see the TCC line pressure on your next log.

i wonder if there is something you picked up from that ctsv file that i didn't get into my car?

this is the first log i have seen where someone got a tripple disk to hold under 70mph. it would be nice to figure out how/why it is working for you.

[parish8]

Hey Parish, looking at your tune,I see some obvious stuff to help the drivability on decel. Ican increase the ct downshift time so its not so abrupt. I also made some changes since the last tune postedas well. Ill post it up.Gonna try someof your CT shift times tomorrow.

i think some of your decel stuff is the lock up kicking on and off. my car was almost undriveable after putting in the converter but after many changes i really like it now. seems like your part throttle shifts are too high.

[camaro1]

gm service manual 6l80/90 tcc description:

• A torque converter with an electronically controlled capacity clutch (ECCC). ECCC was developed to reduce the possibility of noise, vibration, or chuggle caused by TCC apply. In a torque converter with ECCC, the pressure plate does not always fully lock to the torque converter cover. Instead, the pressure plate maintains a small amount of slippage. In RWD 6-Speed transmissions, this slippage can range from 0-50 RPM. Full lockup (0 RPM slip) is still available on some applications. TCC may apply in 2nd, 3rd, 4th, 5th, or 6th gears. The specific TCC apply points and the amount of clutch slippage are determined by a number of operating conditions, including throttle position, vehicle speed, gear, as well as specific vehicle application. Transmission fluid temperature will also affect TCC apply points.


what 6l80/90 uses this full lockup feature??,, even if it was a truck file someone should be able to transfer that part of the code,, or just flash the tcm with the truck file and swap over all the shift speed tables

[Adam@ST]

Did you look at the last tune?Made some changes from the first one posted. Im going to rework some of the neg ramp back into the tcc tomorow just for a feeler. I ll try to datalog the tcc pressure in the morning.

For what its worth,this is a KB car making over 550 rwhp,so power is on tap. Adam

[Adam@ST]

i think some of your decel stuff is the lock up kicking on and off. my car was almost undriveable after putting in the converter but after many changes i really like it now. seems like your part throttle shifts are too high.

The shift points were from the caddy. I did make some changes,and reposted the tune.The harsh shifts are almost gone now.

[parish8]

hey adam, please dont forget about us. a log with the tcc line pressure would be sweet.

you seem to have a set up that works and it is the first i know of. it would be great to figure out what is diferent.

[Adam@ST]

I didnt forget. I have been working a ton the last few days. I had a issue with the alternator, and it wont be in til Monday, car is down til then. I will say this, I tried to ramp the - numbers on the tcc ramp table. Doesnt work, the convertor began to surge again.The tables need to be at 0 on the neg side. I ll post another log and tune Monday. Thanks Adam

[01 MidMet WS6]

Here is a tune from a 08 that I have been working with. It runs pretty well and makes around 525whp on a 100hp shot. I too had to disable up CT downshift and upshift TM to get make it shift like it should. I have converter slip at all times and it drives me nuts. Is there a way to eliminate the 10-80 rpm slip at cruise?

Parish8,

I used your config file and did some data logging on the way home, you can see in the run there is some cruise as well as a couple of WOT pulls for fun. One more thing to think about as well. I know that you stated it needs more line pressure to hold the converter engaged but you have to remember in addition to the line pressure there is an apply solenoid that is duty cycling that pressure to feed the clutch. I did not see it monitored in any of your logs.

[Adam@ST]

hey adam, please dont forget about us. a log with the tcc line pressure would be sweet.

you seem to have a set up that works and it is the first i know of. it would be great to figure out what is diferent.

Hey Parish, hows the trans doing??

[parish8]

Hey Parish, hows the trans doing??

funny you ask. i just got done pulling it out. didn't take as long as i thought it would. no new issues with it, it has been slowing getting worse not holding gears at part throttle. that kind of thing.

i finialy got around to playing with the wires i tied in. using a 15ohm 100watt resistor inline with the psc1 gives me an aditional 40-50psi of actual line pressure. i hooked a switch to a relay, the relay adds in the 15ohms to the pcs1 circuit AND grounds the lock up solenoid but it does it thru a 2ohm 100watt resistor. now i can flip that switch and get lock up and extra line pressure any time i want.

i did a little tuning and got up to 10psi so around 600rwhp and the lock up was still holding. actual line pressure was still only 120psi or so, i think i am going to try and drive that up a little higher.

next i tried it down the highway. it locked it up solid but within a couple of miles it set a code and put it into some kind of limp mode.

next i tried programing the lock up to come on at 50mph in 6th i got up to about 60mph, it was pulsing on and off. i fliped the switch and it locked up solid and stayed locked up for 20 miles. no codes, no slip. ahh, sweet lock up.

i did try a run at the track where i locked it up mid 3rd gear(1/8th mile) but i didn't get conclusive results. i am having fuel pump issues so the test was inconclusive.

i knew i was pulling the tranny so i got gutsy and tried locking it mid 2nd and keeping it locked thru the 2-3 shift. it just released but that doesn't suprized me. my tranny is having a hard time shifting without doing oddball stuff like this. i suspect the lock up is taking up some of the oil and i will need to drive the pressure up quite a bit higher.

tranny is going to get freshend up, then doing drag week, then i might get ballsy again and try locking thru the shift. i will try it on low boost.

i would love to have control of this stuff with the computer. maybe hptuners is working on it?