4L80E WOT Lockup Tuning Help :(

Hey guys,

I'm trying to tune the lockup on my 4L80E/Precision Triple Disc setup. I'm wanting to lockup the converter clutch right after the 1-2 shift. So far i'm having mixed success. In Normal Shift mode, the clutch is FAIRLY consistent to lockup, but in Performance Mode it's very hit/miss. One pass it will lockup fine, next pass it won't. Looking at the Log, the TCC isn't being commanded to lockup on the times it didn't happen.

I belive I've got the MPH/TPS table setup properly....but not sure, i've never tuned a WOT lockup setup before.

I have attached the tune file, and have a log as well but will have to attach it later as it's on a different PC.

This is a Turbocharged LQ4/80E on 10psi, just FYI. Feel free to comment on other portions of the tune if you see anything that might be odd. Car runs great with this tune, just trying to get that lockup right.

Thanks in advance guys!

Attached is the Log demonstrating the Lockup issue, along with my config file. The TCC Lock up 2 file demonstrates it working properly, the other log file has a few hits where it does not lock for some reason. Nothing is changed between the runs, it simply won't lock sometimes, others it will.

I don't know what could be making it lock up inconsistently. My suggestion is to NOT lock it under WOT at all. If Precision built it specifically and correctly for your setup, then there is little to gain by locking it up. You're also gambling with a stock 80E input shaft and locking the converter under WOT.

Your VE table is interesting. It could use some tweaking. Same with your Open Loop EQ table. Looks like you're using that table for power enrichment instead of the actual Power Enrichment tables. It seems to be working good for you, so just stick with it.

Thanks for the advice :).

I wasn't aware the 80E's input was such a weak point, so it's definitely something to consider now indeed. I seem to have the issue resolved after tweaking my MPH tables a bit, seems as if the ECU is a bit sluggish on commanding the lockup. Moving the MPH's down ~5 appears to have cured it, so far anyhow.

You are correct, i'm using the Open Loop EQ Ratio table for my boost enrichment as well. Pretty much Open Loop, Speed Density. I do have operating O2 sensors, but the issue I was having in closed loop was, my LH O2 sensor is located in the Downpipe, and the RH O2 sensor was in the factory location. The RH trims I had down to 1-5%, but the LH was always high at 10-15%. I attributed it to the fact that the LH sensor was further downstream in the exhaust flow and therefore the readings were a bit laggy and skewed. The issue was, under WOT the ECU is applying the learned trim values (+5% RH, +15%LH) and running it very rich. I have had better results leaving it in OLSD, however I much liked the fuel economy and functionality of the Closed Loop operation. I wish there was a way to keep the fuel trims from being applied under WOT Accel/Decel?

Here is a pass locking it up in 2nd onward. I had the shift lock set to disable, so it unlocks after the shift (i'm assuming because the hardware can't unlock fast enough to beat the 2-3 shift), then relocks in 3rd. My MPH was set a bit high in 3rd so it takes a moment. Sounds kinda odd with all this happening, but seems to work good. I netted 2 MPH from last time out, no changes and very similar weather.

The stall converter was purchased used, and was setup for a different power level/vehicle, but seems to function great in mine as well.

http://www.youtube.com/watch?v=R0I4cRUms3g

It sounds like the transmission in my buddy's Hemi Ram, haha.

Did you gain any ET? or just gain MPH?

It's hard to say for certain, as I didn't note the weather conditions exactly. However, it was within 800ft when I ran no lockup vs. locked up. It looks as if .2 and 2-3 mph or so. That's locking in 2nd and 3rd.