LBZ: Need Advice, New to Tuning

[macanic21]

Hey Everyone!
Could you guys take a look at these tunes and give me your thoughts?


I'm having specific trouble with the transmission tuning. I would like to lower the shift points in T/H mode. I tried several things including copying and pasting the points from A to B. However, it always seems to hit some point where it gets confused.



I haven't tried the one I attached but I just manually lowered the upshifts so I'll see if this works.



I can't take credit for the engine tune. I got the base map from this guy
https://www.youtube.com/watch?v=HKu80j0bUHk
and added the MPG timing bump form someones tune in the library here. I added my touch to the vane position and desired boost to get it to drive more how I wanted.

 

[JoshH]

You need to change upshift and downshift speeds.

 

[macanic21]

Yeah, I think I may have overlapped a down and upshift speed. I think I'm slowly getting inside this things head...

How does it change shift points in manual mode? I see the 1-2 shift has patterns E-H "mode 2". If this is it, how does it modify the rest of the gear points?



Is there a guide somewhere so I can figure out which PID to log for what? I'm still struggling to figure out how to log and read playbacks. Is there a way to view maps live to see where the engine is running?

 

[2004LB7]

My tests indicate that manual mode shifts are based off the normal shift schedule

 

[macanic21]

OK, so then why does it not upshift to the same pattern?

 

[2004LB7]

Manual mode just restricts the highest gear. That is all. It doesn't determine the upshift or downshift schedule. That is under the other, normal, T/H or 4low schedule

 

[macanic21]

Do you know where that setting is?
How do pullers prevent downshifts?

 

[Dozerboy]

They don’t other by running in 3rd gear so the rpms are high and it don’t need to down shift.


Sent from my iPad using Tapatalk

 

[macanic21]

I noticed I'm not getting out to 120mm3 at WOT. Is this a limiter or improper setup somewhere or just typical? I attached the log file in a .zip folder.

 

[macanic21]

Also, trying to bump the shift points to 3500 in order to test fueling. But I'm hitting a defuel from something. Any ideas?

 

[macanic21]

OK, I got the fueling worked out for the most part. it still falls off a little but this might be physical limitations also. I'm mainly working on how the boost rolls in at part throttle to try to up the efficiency.



I have spent "a lot" of time on the transmission tuning. This seems to be harder than the engine, at least for me. I'm getting it pretty decent at this point. My goal is to lower RPM's and increase efficiency at light throttle. Also to improve and normalize shift points for better WOT performance. I've settled on lockup in 3rd gear at least at this point. My theory is to split 3rd gear with lockup. I think this will work in the long run because the gap in the gearing between 3rd and 4th is pretty large.

My only other thinking is that I may be able to lock in 3rd, then unlock going into 4th to allow the upshift sooner, then split 4th again with lockup. I'm not sure if this would be more efficient but it would put more wear on the TCC clutch. I'm also not sure if I could get it to do this smoothly.


If anyone wants to take a look I'll post up what I have done up until now.

 

[macanic21]

Alright new question:
I'm having an issue with TCC lockup when the transmission is cold in 3rd gear. It always shudders like it tries to lock, backs off, then locks. Any ideas?


I'm locking up in the middle of third. But I also have the same issue if I tell it to lock as soon as it hits 4th.

 

[2004LB7]

OK, I got the fueling worked out for the most part. it still falls off a little but this might be physical limitations also. I'm mainly working on how the boost rolls in at part throttle to try to up the efficiency.



I have spent "a lot" of time on the transmission tuning. This seems to be harder than the engine, at least for me. I'm getting it pretty decent at this point. My goal is to lower RPM's and increase efficiency at light throttle. Also to improve and normalize shift points for better WOT performance. I've settled on lockup in 3rd gear at least at this point. My theory is to split 3rd gear with lockup. I think this will work in the long run because the gap in the gearing between 3rd and 4th is pretty large.

My only other thinking is that I may be able to lock in 3rd, then unlock going into 4th to allow the upshift sooner, then split 4th again with lockup. I'm not sure if this would be more efficient but it would put more wear on the TCC clutch. I'm also not sure if I could get it to do this smoothly.


If anyone wants to take a look I'll post up what I have done up until now.

I've tried a shift strategy similar to what you discribe. Locking and unlocking between shifts to kind of simulate splitting gears. Never got it to run as planned. Because of the gear ratios and the unlocked slip of the converter it would never "split" properly.

I put together a number of Excel spreadsheets to help with the shift tuning and prevent overlap and help visualize with graphs the whole shift schedule. It improved my shift tuning greatly.

Once I got it all close, I found even a half mph shift up or down change in the table could be make a large difference in response

I'll see if I can dig it up and post it here

 

[2004LB7]

here is the stripped down version of the excel sheet I used to do my shift points. it's helpful because it allows you to overlay upshifts, down shifts, converter lock and unlock all on one graph. that way you can see if there is any weirdness or something you may have forgot.

My shift schedule is now vastly different then stock but i've put stock values in for the upload here.

Fill in your tire and differential values on the first tab then play around with your shifts on the second. the two sheets are linked so you will want to make sure both are filled out.

for reference, I have no upshifts, down shifts, locks or unlocks cross over each other and it seems to work really well on my truck. it always seems to know what gear to be in and doesn't hesitate or hunt for the right gear. it is actually a very simple shift strategy to make and tweek

 

[macanic21]

Thanks a lot! I'll take a look at that. Funny thing is i started building my own spread sheet but yours is way more advanced then what I have so far. I was just graphing shift points.

It seems that my issue may have just been a learning issue. I let it run for a while and it got better. I thought it was just because it warmed up at first, but multiple cold starts have proven otherwise. Does this have to learn TCC lock in every gear?

I think I'm just going to split 3rd or 4th. I don't want to put that much wear on the TCC. I'll post your sheet up with my info and my tunes when I get a chance so you can see where I'm at.

 

[macanic21]

Ok, I'm still getting a hitch during lockup when cold. Any ideas?
It seems to get about 75% into lockup, then it goes back to 0%,then locks up completely. This happens quickly and is not clutch slip because of a mechanical problem.

 

[macanic21]

Also, still only getting out to about 110mm3 of fuel WOT. Is this normal?

 

[2004LB7]

Also, still only getting out to about 110mm3 of fuel WOT. Is this normal?

Take a look at your B1115 table. looks like you max out at 664 ft/lbs. if you cross this over to B1102 it is only 102.3 mm3

 

[2004LB7]

Ok, I'm still getting a hitch during lockup when cold. Any ideas?
It seems to get about 75% into lockup, then it goes back to 0%,then locks up completely. This happens quickly and is not clutch slip because of a mechanical problem.

probably need to log it so you know exactly where in the tune this is happening

 

[macanic21]

Yeah I went back through and upped some limits again like you mentioned. Here are my latest updates for the trans and engine.


Anything specific you would suggest logging? I'm assuming engine RPM, TCC pulse, gear? I can upload logs also if you are interested.


I've been logging the ECM but have not done much with the TCM so that is where I'm headed next. Is is possible to log both at once?