Looking for WOT 4L60e scanner logs with input/output rpm's logged

[slarsen47]

I have only made two full quarter mile passes on my 4L60e with 3600 converter.

I am looking for other WOT 4L60e scanner log files with the transmission input and output shaft rpm's logged.

If you post your log file I will prepare a 1-2 and 2-3 shift time chart as shown below.

The two charts below show the shift time to complete on my 2002 Camaro on a 11.40 pass.

Hoping to see a few other logs to see what is typical or normal time for shift to complete.

The chart is prepared by exporting scanner log file to excel.

I will do this task and post it here if you can provide the log file.


1140 1-2 shift slip.jpg



1140 2-3 shift slip.jpg




EDIT: December 11, 2023

The 4L60e in my car does NOT have the capability to report input shaft data, so this analysis is misleading and NOT representative of actual transmission slip.

[slarsen47]

Back to the top.

[TransGo Robert]

Sorry I don't have what you are looking for, but wanted to comment that you can do the same without exporting it to excel right in the HP Tuner log viewer using a math channel.

[chadtunes]

I've been doing a fair amount of logging on my L86, diagnosing issues after an engine install..

Will normal driving logs with shaft speeds do you any good? I just happened to be looking at my shift times and TCC slip in these.

I can PM you my email; I can't attach files for some reason, and send what I have and I can get you some WFO logs.. Give me a few days for that, trucks in the shop getting the trans looked at.

[TransGo Robert]

I've been doing a fair amount of logging on my L86, diagnosing issues after an engine install..

Will normal driving logs with shaft speeds do you any good? I just happened to be looking at my shift times and TCC slip in these.

I can PM you my email; I can't attach files for some reason, and send what I have and I can get you some WFO logs.. Give me a few days for that, trucks in the shop getting the trans looked at.

All you need is to record the input rpm and output rpm and then create a math channel that divides input by output and you'll have what you need. If you don't know how to create a math channel let me know I'll explain. If you want to email me your file my address is [email protected] but the math channel if I create it will only work for me. You have to it on your own computer in order to be able to use it.

[dian]

this is very interesting. so it takes 1.5 and 2.5 seconds to shift? how does that compare with rpm drop? i thought my 2-3 shift was about 0.3 seconds based on that.

thats with a stock converter, though.

[TransGo Robert]

this is very interesting. so it takes 1.5 and 2.5 seconds to shift? how does that compare with rpm drop? i thought my 2-3 shift was about 0.3 seconds based on that.

thats with a stock converter, though.

Looking at the RPM drop you will only be able to see the first half or so of the shift. Not sure why the OP's shifts were so long, there was never a log posted on here. By the way the length of the shift is going to vary a whole lot from one to another. Lots of internal things make a big difference, and then the variation in power and weight from one vehicle to another makes a world of difference as well. The computer on a 4L60E has very little control of the length of the shifts unlike on modern transmissions, all it can do is lower teh EPC amperage. It is much easier to shorten the shifts by modifying the unit itself.

[Fast4.7]

Looking at the RPM drop you will only be able to see the first half or so of the shift. Not sure why the OP's shifts were so long, there was never a log posted on here. By the way the length of the shift is going to vary a whole lot from one to another. Lots of internal things make a big difference, and then the variation in power and weight from one vehicle to another makes a world of difference as well. The computer on a 4L60E has very little control of the length of the shifts unlike on modern transmissions, all it can do is lower teh EPC amperage. It is much easier to shorten the shifts by modifying the unit itself.

One thing to remember on the 4L60E and 4L65E, the input shaft rpm is calculated, not measured like it is on a 4L80E. GM used the PCM to calculate the input shaft speed off engine rpm. Once a higher stall converter goes into place the PCM often sees the added slip as the actual shift not being completed. The shift adaptives thus should be disabled when running a 4L60E with a loose converter.

[Fast4.7]

Looking at the RPM drop you will only be able to see the first half or so of the shift. Not sure why the OP's shifts were so long, there was never a log posted on here. By the way the length of the shift is going to vary a whole lot from one to another. Lots of internal things make a big difference, and then the variation in power and weight from one vehicle to another makes a world of difference as well. The computer on a 4L60E has very little control of the length of the shifts unlike on modern transmissions, all it can do is lower teh EPC amperage. It is much easier to shorten the shifts by modifying the unit itself.

One thing to remember on the 4L60E and 4L65E, the input shaft rpm is calculated, not measured like it is on a 4L80E. GM used the PCM to calculate the input shaft speed off engine rpm. Once a higher stall converter goes into place the PCM often sees the added slip as the actual shift not being completed. The shift adaptives thus should be disabled when running a 4L60E/4L65E with a loose converter. The ratio logs he has generated in the first post are including the converter slip. There is actual programming that HP Tuners does not have defined in their program that are set for converter slippage. If that were accurately calibrated, the converter slip would be compensated for. In addition the converter slip also works with another table that is part of the torque management. GM has a table that roughly calculates converter STR for torque management reasons. The more converter slip rpm the higher the torque converter torque multiplier used.

[TransGo Robert]

One thing to remember on the 4L60E and 4L65E, the input shaft rpm is calculated, not measured like it is on a 4L80E. GM used the PCM to calculate the input shaft speed off engine rpm. Once a higher stall converter goes into place the PCM often sees the added slip as the actual shift not being completed. The shift adaptives thus should be disabled when running a 4L60E with a loose converter. The ratio logs he has generated in the first post are including the converter slip.

Correct, on older applications like that 2002 from the OP, no ISS, on the newer ones they have one which makes it possible to calculate the ratio accurately even when the converter is not locked.

[Fast4.7]

Correct, on older applications like that 2002 from the OP, no ISS, on the newer ones they have one which makes it possible to calculate the ratio accurately even when the converter is not locked.

Correct, IIRC the input speed sensor did not come along until GM went to the 4L70E. So only a few years came with the ISS. The 4L80E had an ISS from day 1 if memory serves me correctly. I know my 94 G30 had an ISS. The shift time calculation on those units is very accurate as is the converter slip rpm calculation. With an ISS both are calculations from physical sensor measurements of engine rpm, turbine shaft rpm and output shaft rpm.

[TransGo Robert]

Correct, IIRC the input speed sensor did not come along until GM went to the 4L70E. So only a few years came with the ISS. The 4L80E had an ISS from day 1 if memory serves me correctly. I know my 94 G30 had an ISS. The shift time calculation on those units is very accurate as is the converter slip rpm calculation. With an ISS both are calculations from physical sensor measurements of engine rpm, turbine shaft rpm and output shaft rpm.

Yes from day 1 on the 4L80E, for the 4L60E it started in 2005 but it depends on the applications, it was a gradual thing, some had it some did not until 2007 where they all have it.

[kingtal0n]

My 4l80e does not correctly calculate shift time for fourth, the most slipping gear with the least drop difference. I don't think it looks at input shaft speed at all in my ECU 411 just the rpm drop some amount. Maybe its an artifact with 2-bar os or something but it definitely never worked the other gears do though.

[TransGo Robert]

My 4l80e does not correctly calculate shift time for fourth, the most slipping gear with the least drop difference. I don't think it looks at input shaft speed at all in my ECU 411 just the rpm drop some amount. Maybe its an artifact with 2-bar os or something but it definitely never worked the other gears do though.

On a 4L80E the input sensor is not reading the input shaft,it is reading the forward drum which is overdriven in 4th gear so that complicated things a bit to figure things out during the shift.

[kingtal0n]

Oh yeah I never really thought about that. Interesting

[dian]

so does the 2-3 shift actually happen in 0.1 sec in the second graph? what might the engine rpm look like? small drop, large drop, small drop in 0.3 sec overall? i somehow doubt the 0.1 sec, with all the release and apply stuff going on.

whats the fastest 2-3 shift a built 4l60e can produce?

[slarsen47]

Hi all............

I have been away from the car scene since my last post but am back to working on the cars up here in the cold frozen north.

The procharged 4L60e car runs and drives great but the apparent shift/slip time is still a big concern.

Work has now resumed on my 98 hardtop with a Huron turbo kit, iron 6.0, Moser 9 inch and 4L80e (10.0 goal).

Thanks for the replies. Great info I was not aware of.

In response to the reply suggesting that I have not taken into account converter slip, I am logging engine rpm, input shaft rpm and output shaft rpm separately as per the list of logged parameters. The scan file clearly shows the converter slip separately.

But apparently the input shaft rpm is calculated by the pcm as opposed to being a sensor value?? My 2004 4L60e was built as a level 4 and may have the sensor??

I have spoken with my trans tuner in the past few days and he is firm that my 4L60 is built to work without torque management.

But I remain unconvinced until the data proves otherwise, if that is possible.

Here is my tune and data log for the 11.40 run that I pulled the data from to show the apparent lengthy shift time as per graphs.



Aug 4a 2023 add fuel wrote.hpt

1140.hpl

[kingtal0n]

During the shift there should be a slight spike in boost pressure but I see none indicating a leak. The IAT rises rapidly also indicating a leak or poor intercooling.
You should perform a pressure test, fill the compressor cover with air pressure through the intake manifold to find all leaking. With even the cheapest possible ebay intercooler 3x15x24 or 3x12x32 it can maintain a better IAT than yours at 20psi of boost.

2. The trans fluid temp rises rapidly after the run indicating slippage or poor energy management. The converter may be inefficient or the trans cooler may be very small or there is something slipping excessively.

3. Need to log Force Motor Current to see what pressure is being commanded. Without that there is no way to tell if the slip is related to trans internal issues or simple lack of commanded pressure rise.

Thoughts
The 1-2 shift does look like a slip. Qualitatively anyways. I would expect a more firm slope than what I see. At the end of the day all you can do is command max pressure though, unless you build the transmission yourself and modify the pump and boost valves and clutch packs and so forth.

[TransGo Robert]

The transmission input shaft speed is a made up value that at time is no even close to being possible. Your computer is a 2002, even if the transmsision had been rebuilt with a 05-up pump and input shaft that use a turbine speed sensor there is no circuitry for it in the computer or wires for it in the vehicle's wiring harness. You can see how bogus the reading his on the first set of upshifts 1-2-3 where under moderate acceleration the input shaft is turning faster then the engine up to 2000+ RPM faster at a certain point which is only physically possible when you are coasting down, now on acceleration. The computer never commands lock-up so you can't ever calcutate the gear ratio accurately. Your 1-2 shift sure seems sloppy but without all the transmsision parameter it is a bit hard to say just how bad it is. We would need shift solenoid command and pressure solenoid command to better evaluate things. No matter what, unless the pressure command is all wrong, there is little you can do on those tuning wise to help a 4L60E shift quicker, it would need to be modified internally.

[slarsen47]

Thanks for info and clarification.

The fact that input shaft rpm is NOT a sensor value makes trying to assess the shift time of minimal value and may in fact be misleading.

Are the shift solenoid command and pressure solenoid command parameters I can log with the 411 pcm?

Regarding intake air temp, I am using the stock dual intercooler setup from procharger. It was a hot day and the intercoolers would likely have some heat soak just driving to the staging lanes and doing the burnout. Engine coolant also was quite high to start. Transmission cooler needs improvement. Will add force motor current to list of parameters. Stock pulley on the procharger is only making a bit over 6 psi and belt slip (even with the 8 rib manual adjuster) is possible. I have not really cranked the adjuster!

Having used all of the available 0-5v inputs (using egr and fuel tank pressure) except the a/c one is there an easy way to data log the transmission pressure?

If I had not made the attempt to chart the shift time, I would not be aware of any potential issue. The shifts on the two full throttle passes I made seemed normal. On the street shifting and lockup are perfect.

The issue ultimately will be the longevity of the transmission and that is where understanding and optimizing line pressure and torque management become important. From what I am reading not sure if changing pulley to get 10-12 psi is a good strategy for the stock cammed 5.7 or the 4L60e staying healthy.