2WD RCLB LBZ Build
- Thread starter othrgrl
- Start date
We did the reverse on a 1500 chassis with 2500 spindles. It bolts right up but was about 1 degree out of spec. I forget which way though...
Yes, 2" sides is the shallowest they make, so they use 2 of those.
Shields, we aren't - I was trying to go to Darlington again today but the track got rained out. Also this TCM is still doing whatever it wants to. It won't do a 2nd gear start - won't hit 2nd until like 15mph. I even set each table to the WOT shift point across the board so:
1-2: 0mph
2-3: 63mph
3-4: 86mph
4-5: 115mph
5-6: 318mph
From 0% to 100% throttle in all modes, and in the WOT shift tables. WOT RPM tables are 0RPM for 1-2, 4800 RPM for 2-3, 3-4, 4-5, and 8000 RPM for 5-6. Yet it will still start in 1st and go through all the gears and be in 6th by 60 with light throttle. Even tried setting WOT threshold to 10% and even 0% throttle - still the same. It is like it is running on a different default mode that I can't see in the tune file with EFI Live. Have tried 2 different TCMs with 2 different OS, one being an OS we have used and had good luck with in the past. Even tried to ground PIN 42 for the 4Lo input signal and set the T-case ratio in the tune to 1:1 - still did the same.
On the 10.49 pass it started in first, hit 2nd around 4800, hit 3rd around 4800, hit 4th around 4800 86mph, but then immediately went to 5th and 6th before the 1/8 and bogged the rest of the way through the 1/4.
I was planning to launch in 1st (even though I would much rather be launching in 2nd) in M4, then tap it up to 5 so it doesn't bog down again.
I would definitely interested if you decide to go a different route or bolt pattern Dustin.
This is one reason I am happy I have a 5 speed. The 6 speeds don't seem to follow the commands you put in the TCM.
This is one reason I am happy I have a 5 speed. The 6 speeds don't seem to follow the commands you put in the TCM.
I'm sure you will figure it out. 
What you've done so far is amazing, I need to get back out there and check it out and show you my new toy.:joker:
What you've done so far is amazing, I need to get back out there and check it out and show you my new toy.:joker:
Finally got it figured out. The transmission was going into "Engine Default Shift Mode Pattern" and I had to chase down why. Turns out that on an LBZ the MAF is used to calculate delivered torque and if you delete the MAF the ECM will put the TCM into that shift pattern, which we can't see or tune with EFI Live. We are wiring the MAF back up right now and are going to verify that the Trans goes into Normal and TH mode and shifts as it should.
That had to of been fun to track down! Hopefully that solves your issue and you get the 2nd gear start you want! :thumb:
Only got it back on the track once last year after wiring the MAF back in. Track was cold and it was like it was on ice. 2 weekends ago we went to Diesel Truck Wars and on the first pass we trapped 109mph in the 1/8. 2nd pass blew an up-pipe bellow because the turbine housing was able to rotate and let them stretch out. Got a 1.15 T6 housing for it, a T6 to dual 2.25" adapter and some new bellows and remade the piping with a support from the T6 adapter to the turbo mount bracket. Just gotta fab the new 5" hood stack pipe next week and get it back on a 1/4 mile track.
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Gonna talk to them about making a 1/4 pass on Sunday.
Gonna talk to them about making a 1/4 pass on Sunday.
