4l80e Swap Frost/PCM of NC Harness Tuning

[alexl226]

07 Suburban - Turbo - 4l80e swap - circle d 2500 converter - 3.73's - PCM of NC relay harness


Anyone who knows how to tune these please let me know, willing to pay top $. I can dial in the motor but transmissions are not for me.

It's my daily and I'm currently driving it. Trans was swapped about 2 months ago. I dont beat on it and dont ever think I did a full WOT pull through the gears ever. But I've noticed the truck seems to be loosing pulling force from the seat of my pants. Stabbing the throttle doesnt seem to putting the power to the ground like it used to be.

All codes and slip test's required for the harness should be eliminated shift times have been shortened some and trq management was removed. I started to interpolate the force motor table but the values I was entering were much different than the current 60e. I haven't touched the force motor or shift pressure modifier tables yet because all the tunes in the repository have completely different axis.


Burb 1-7_new shift_new pressures_gears.hpt - current tune

Burb 1-7.hpt - previous tune

[Lakegoat]

I have a 4L80 and will try to help if you can tell me your tire size (diameter) and what you want for WOT shifting rpm. I can send you the tune to compare after I make the changes. You will still have to make some little tweaks to get it where you like it. I am using the PCMof NC relay harness also with circle d 3000. I only lock the converter in 4th about 45mph.
Do you have HPTuners?

[alexl226]

Yes sir I have hptuners. I've found some tables last night on ls1tech where I used some of his pressure values. I used bluecats trans tuning program to get my shift speeds pretty close then fine tuned them. I'm running 35" tires. The trans felt pretty good without messing with the force motor and pressure modifier tables. TCC lockup seems to be working. My concern was with the force motor and pressure tables and my general lack of knowedge of trans tuning, I feel like I could be missing something stupid!

A quick stab of the throttle feels very dampened opposed to what it was like when I first swapped in the 80e. This is with the converter unlocked. There is no real jump from the truck anymore, rpms just shoot up to the flash 2600 and keep rising and it smoothly but slowly increases in speed. I dont beat on the truck, its my daily driver but when I used to get into boost the front end would lift up and the truck would slightly twist from the torque. That all seems to be gone. I dont notice however any jerkyness like I've noticed with a slipping trans in the past, however possibly the very large and heavy tires are hiding some of that? Attached is my current tune for 3.73 rear end and 35" tires. I've now modified the shift speeds, times, pressures, pressure modifier, force motor, tcc duty cycle and apply/release speeds and it appears hptuners now allows you to change the gear ratios. I've been failing to find an a tune in the repository that even comes close to matching my axis for all the pressure tables so I used a file I found on ls1tech (your on that thread too). They all seem to vary vastly from what was originally on my tune. I changed the pressure tables last night and noticed the truck feels much better below the torque converter stall speed, but it still feels like it's failing to put down the power when I get into it. As always I'm more than happy to compensate you for your time and greatly appreciate any help. Oh btw desired WOT shift is only like 5500 rpm.


Burb 1-7_new shift_new pressures_gears.hpt - current tune

Burb 1-7.hpt - previous tune



Also, can someone help me log output shaft rpm because I dont have the front ISS hooked up, shouldnt I be able to just switch that to the output shaft rpm with the correct gear ratios and monitor slip that way? Or actually shouldnt the tcc calculated slip now be right with the correct gear ratios entered?....I know I'm all over the place, just trying to wrap my head around this stuff!

[Lakegoat]

If something has changed in the trans to make it slip, changing the parameters is probably not going to help.
We have a bunch of differences in our trans tunes so I will take a look. I didn't change the force motor tables from the 4L60.
Compensation is not necessary. A lot of guys on here have helped me.
Let me see what I can figure out.

[Lakegoat]

Check this out and compare the tunes starting with the speedo. I like to keep a lot of the tables the same --Normal, Pattern A and Pattern B as you will see.
There is a bunch of changes, so be sure and save your tune just in case this is not what you like. It has worked for me so far. I still use the torque tables in my street tune, but not my drag tune. I do still use the abuse tables in both.
I did use your mph numbers for shifts.

[alexl226]

I realy appreciate it. It seems most people with the harness aren't changing the force motor tables. If that's the case, I'm not sure how I would have damaged the trans? Isn't that the table that controls pressures while cruising not just shits?Since day one it shifted what I thought was hard (which from what I understand is not normal for 60e to 80e swaps as 80es are typically really lazy).The truck would lunge forward when it went to complete the shift. With the new pressure data I've enetered it Now shifts hard. A solid thud into the next gear, not a lunge forward. Before it almost felt like the converter was locking during shifts or something was still spinning with some weight when it engaged the next gear. I was able to make it shift like stock by modifying the shift pressure tables. It seemed to run fine but after a few weeks it started to feel like I was loosing the ability to put the power down..

[alexl226]

And I'll take a look and let you know. Thank you sir!

Also, the tq managment was causing some really weird issues for me. When it would shift it seemed like the torque reduction happened for a second or 2 after the shift completed. I had it completely removed from the 60e and put it back in to try to soften the shifts, but noticed it lagged behind the shift and made it feel horrible.


Couple questions

How did you get VSS output pulses per tire. I realized I missed this on the original tune but wouldnt it just be the pulses per rev X rev's per mile? So 40 ppr x 576.25 rpm = 23,050 ppm?

Final drive ratio for trans should be 3.73 too?

Should I copy over the d1 and d2 tables from the normal shift tables for 1-2 and 2-1?

Since mine is a truck pattern Y is my tow haul mode. It also states i shouldnt change the drop downs of which pattern controls the shift for x y and z. but you have them all at X? would this mess things up with the tow haul mode? why do they suggest not to change it?

Noticed you decreased alot of the shift pressures for pattern x. I also noticed most 4l80e files only go to 4XX ft lbs of torque on the scale. just trying to make sure it wasnt a copy past error?

That's all I have time to look at right now. Again thanks for you help and sorry for the 21 questions, I am just hungry to learn...

[Lakegoat]

And I'll take a look and let you know. Thank you sir!

Also, the tq managment was causing some really weird issues for me. When it would shift it seemed like the torque reduction happened for a second or 2 after the shift completed. I had it completely removed from the 60e and put it back in to try to soften the shifts, but noticed it lagged behind the shift and made it feel horrible.

Might have something to do with engine torque--timing reduction. ?


Couple questions

How did you get VSS output pulses per tire. I realized I missed this on the original tune but wouldnt it just be the pulses per rev X rev's per mile? So 40 ppr x 576.25 rpm = 23,050 ppm?

I plugged in the numbers 3.73 and 35" tire, selected commit and let the computer calculate it.

Final drive ratio for trans should be 3.73 too?

Should I copy over the d1 and d2 tables from the normal shift tables for 1-2 and 2-1?

Since mine is a truck pattern Y is my tow haul mode. It also states i shouldnt change the drop downs of which pattern controls the shift for x y and z. but you have them all at X? would this mess things up with the tow haul mode? why do they suggest not to change it?

I thought this was a performance truck---didn't know you were using the haul mode. You should keep those stock.

Noticed you decreased alot of the shift pressures for pattern x. I also noticed most 4l80e files only go to 4XX ft lbs of torque on the scale. just trying to make sure it wasnt a copy past error?

I have a built 4L with shift kit, and my tune is probably not going to work for you if you have a stock trans. This is a street tune and my trans shifts quick enough. Drag tune the base is all 89.9. Downshift doesn't need to be maxed.

That's all I have time to look at right now. Again thanks for you help and sorry for the 21 questions, I am just hungry to learn...

I replied under some of your questions. I think you should find someone local that can ride in your truck and tune it until you get it to where you are happy with it. Sorry I wasn't much help.

[alexl226]

Thanks for the help. It's really is much appreciated.

[alexl226]

It's gotten worse. I've stopped driving the vehicle in fear of damaging more parts..RPM's only drop ever so slightly in between shifts. Trans shop is up in arms, dont want to even consider looking at it without me saying it's all my fault...they are trying to blame the fact it's a modified swap, blah blah blah. I have nothing to gain by lying to you guys, this is my only vehicle, I've truly babied the crap out of it the last 2 months. Only ~1500 miles on a factory reman trans and brand new torque converter from circle d...

[Lakegoat]

Go to the tune repository and get a stock tune.

[alexl226]

I've tried. Cant find anything that matches the format and/or axis of my pcm/tcm.

[alexl226]

TPS Check.hpl

Could someone please check this log?

I was testing the TPS sensor. I was getting a P0121 months ago. Disabled the P0101, P0106 and P0121 in the tune and havent thought twice about it. Just want to make sure the TPS isn't causing any weird issues.

[alexl226]

also noticed while I was testing the TPS throughout it's range, the current gear bounced from 1st to 2nd? on the throrrle it shows one, when I let off it shows 2nd. Is that because the engine is off?

[brandon6.0]

Did u set all parameters to what was specified by pcm of nc? I swapped a 80e in my tbss that originally had a 70e. I drove around for maybe 2 months with just there harness without tuning at all. Trans shifted very firm and throwed a few codes but didnt hurt it. Since tuning i set all parameters and just started tweaking shift speed and pressure lil by lil while driving around. I like were its at now. Firm shifts and shifts when commanded. I still think lockup is a lil early but ive been to.lazy to adjust it lol.


Is start fresh with your stock tune with there settjngs and go from there.

[alexl226]

I've noticed something while looking through the logs that my all of my brake apply status bits are flashing on off. Does my vehicle not support those or is there an issue to look into?