New PB

DAVe3283

DAVe3283

Heavy & Slow
Sep 3, 2009
3,781
355
83
Boise, ID, USA
Slowly getting the transmission tune dialed in after the 6 speed conversion. It's still not totally happy or doing quite what I want it to, but it's getting closer. Took 3 tenths off my best from last year at the same MPH just by getting the power down better.

Still could launch a bit harder, and stand to do some suspension work to get that 60' down, but on 35" BFG AllTerrain tires with stock ride height, I think it's doing alright.

I'm the left lane, 12.409 @ 111.26.

20240330_140314.jpg

 
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DAVe3283

DAVe3283

Heavy & Slow
Sep 3, 2009
3,781
355
83
Boise, ID, USA
I do my own tuning. I have slightly refined the tune from when I had it dynoed (789HP, video & tune file shared here: https://www.duramaxdiesels.com/forum/threads/changing-turbo-setup.88837/post-1214877), but not added any fuel. I am out of injector (SAC 75%), my setup should be good to closer to 900HP with bigger sticks.

The truck is stupid heavy (about 8,200 lbs) so it takes a lot of power to hit the same ET as a more typical truck. I run with the lift gate and push bumper on, had over 40 gallons of fuel in it for the run, etc. Just like I drive it on the farm, except I washed the mud off as a favor to everyone else trying to use the track after me ?
 
2004LB7

2004LB7

Super Moderator
Staff member
Dec 15, 2010
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3,058
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Norcal
DAVe3283 said:
I do my own tuning. I have slightly refined the tune from when I had it dynoed (789HP, video & tune file shared here: https://www.duramaxdiesels.com/forum/threads/changing-turbo-setup.88837/post-1214877), but not added any fuel. I am out of injector (SAC 75%), my setup should be good to closer to 900HP with bigger sticks.

The truck is stupid heavy (about 8,200 lbs) so it takes a lot of power to hit the same ET as a more typical truck. I run with the lift gate and push bumper on, had over 40 gallons of fuel in it for the run, etc. Just like I drive it on the farm, except I washed the mud off as a favor to everyone else trying to use the track after me ?
Click to expand...
Awesome. I ask because your times are not that far off from mine up to the 330 mark then you pull away pretty good from there. I also do my own tuning but I only have a stock engine/injectors so there's only so much I can get from it. I'm guessing 450hp. Mine is also about the same weight at 8,200 lbs. The 08 LMM in my sig.
 
PureHybrid

PureHybrid

Isuzu Shakes IT
Feb 15, 2012
3,886
800
113
Central OH
Good MPH, shows potential. What converter? Weight really kills things on the front half, hell I'm right there with you at the 1/8th
 
DAVe3283

DAVe3283

Heavy & Slow
Sep 3, 2009
3,781
355
83
Boise, ID, USA
PureHybrid said:
Good MPH, shows potential. What converter? Weight really kills things on the front half, hell I'm right there with you at the 1/8th
Click to expand...
Ultimate Transmission does their own converters, so I had to call and ask. It uses "a factory orange label stator for an 8.1L trash truck" with a custom impeller they make in-house. They do use an off-the-shelf billet housing, but can't remember what brand they were using when they made my converter. Lockup clutch is a triple-disc setup, again don't recall exactly what was used when they made this converter.

I have been running this converter since 2015, so I can't blame them for not remembering exactly what parts went in it 9 years ago.
 
Dozerboy

Dozerboy

Well-known member
Jun 23, 2009
5,088
682
113
TX of course
I really wanna take my truck to the track, but I just not comfortable doing it. Lots of people around here go. Just to many of them make a lot of power and don't know how to handle it.
 
DAVe3283

DAVe3283

Heavy & Slow
Sep 3, 2009
3,781
355
83
Boise, ID, USA
Dozerboy said:
I really wanna take my truck to the track, but I just not comfortable doing it. Lots of people around here go. Just to many of them make a lot of power and don't know how to handle it.
Click to expand...
We did have 3 people nearly lose it that day, which seemed higher than normal, so I get what you're saying.

Come out to a test & tune / grudge race event with me, and we can line up next to each other. I like to think I know how to handle my truck and am not a danger to the other lane.

Sent from my FlashScan V2 using Tapatalk
 
DAVe3283

DAVe3283

Heavy & Slow
Sep 3, 2009
3,781
355
83
Boise, ID, USA
Got back to the track for my birthday a while back, and with a better launch, got it down to a 12.162 @ 111.58 MPH. Still 8,200 lbs give or take, so I am really fighting physics at this point. It might be fun to take some of the weight out just to get that 11.999 pass one of these days when I get some free time.

 
N2BRK

N2BRK

Well-known member
Dec 31, 2009
2,377
712
113
Any progress on the 6speed tuning? I can't justify the cost, but it would be nice to make for a less "busy" feeling running highway trips :) Plus, I make a crazy amount of boost at highway cruising RPM compared to the "old" LMM, lol. GAWD she's responsive though! hahaha.
 
DAVe3283

DAVe3283

Heavy & Slow
Sep 3, 2009
3,781
355
83
Boise, ID, USA
Unfortunately I have been too busy to finish reverse engineering the GM OS that everyone converts to 6-speed so that I can freely give it away. However, I do have at least basically usable CAX files to edit 6-speed tunes, working with both DuramaxTuner and PCMPerformance files. PCMPerformance will sell you an unlocked EFILive file you can then tweak with my CAX files to shift when/where you want.

I really do want to finish using Ghidra to de-compile the GM OS enough I can clean-sheet the 6-speed conversion, but realistically I don't have the time with my new position at my day job.

I do remember someone (might have been you) wanting the shift time tables for 5→6 and 6→5, but the PCMPerformance tune works so well I have not had to adjust that. It is a little off in my blue truck with the DuramaxTuner file, so I might get motivated to find that & put it in my CAX file one day, but no promises.
 
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