If i was to run a smooth no defuel TCM tune in my truck, would the allison be able to handle it at around 750hp?
Running no defuel
- Thread starter bigbird
- Start date
not shure ? i know i have tried it @ 620 hp and it didnt skip a beat but i will not run it again , for me the ET isnt work the $$$$ risk but the shifts did feel good alot smoother then i would have thought .
What I've been told is that when you get up there in power (and 750hp is up in the danger zone) the biggest problem with no defuel is you run a grave risk of a tie up. The reason is, as the torque goes up, the TCM tries to shift faster, until it tries to shift so fast it's actually in two gears at once resulting in BOOM! You're probably ok with smaller tunes (less than 100hp), although you'll probably have more wear on the clutches. Like others have said, the non-defueled shifts felt much cleaner than defueled shifts, once learned.
I ran it with my PPE on 330hp, but I won't do it again on anything over 90 unless a hardware solution can be found for the tie ups.
I ran it with my PPE on 330hp, but I won't do it again on anything over 90 unless a hardware solution can be found for the tie ups.
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ya but .... it seemed to quick and clean though like a split sec off and it would tie up . it was shifting very fast ... remember the allison was not designed to shift fast . could have worked well just $$ if it didnt i kepped the tune though
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I run no defuel and I am at or above 750hp now. Once the trans learns with no de-fuel I do like the way the shifts feel. Like others have mentioned, shift timing is the real voodoo and the risk is there for tie-up. I have several built 6spd Allisons and have been rotating them in/out and working with my trans man to keep tabs on wear and early signs of distress (also trying different converters to see which ones will lock-up more consistently).
I like that little Disable button :rofl:
seriously though. It works nice but it is scary when the trcuk starts banging off gears. It feels good, but you always wonder if its going to mis that 1 time. Remember, shift timing is done in ms, which is extremely fast and no time for F' ups.
What about raising shift timing a bit, and run no defuel....
seriously though. It works nice but it is scary when the trcuk starts banging off gears. It feels good, but you always wonder if its going to mis that 1 time. Remember, shift timing is done in ms, which is extremely fast and no time for F' ups.
What about raising shift timing a bit, and run no defuel....
GMC_2002_Dmax
The Still Master
If anyone wants to run No-De-Fuel/TCM-disabled on shifts I would suggest having a few spare Allison's lying around for the carnage that will surely happen.
That tune table was in BETA and another tuner let it out of Beta ....................and as all things it is use at your own risk.........:rofl:
You can tune the ecm it to shift just fine with a little defuel, no tcm changes are needed, but maybe taking the easy way out and hitting the disable button in the TCM will work for a while.
Being a betting man that is a bet I would take in a minute, your Allison is doomed and will live a short life..............
Make sure you have Mike L's or BIG DIPPER's number handy, you will need it.
:angel:
That tune table was in BETA and another tuner let it out of Beta ..........
..........and as all things it is use at your own risk.........:rofl:You can tune the ecm it to shift just fine with a little defuel, no tcm changes are needed, but maybe taking the easy way out and hitting the disable button in the TCM will work for a while.
Being a betting man that is a bet I would take in a minute, your Allison is doomed and will live a short life..............
Make sure you have Mike L's or BIG DIPPER's number handy, you will need it.
:angel:
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When will you guys learn that you run no faster with defuel eliminated. The nice hard shift is a tie up that locks the wheels for a millisecond. Any firm shift in the Alli is a tie up. First thing that happens is a twisted spline on the planet and C2 hud. 1100.00 before we even touch the truck. Keep the credit cards handy and tune away.
Remember that no Alli from anyone is gauranteed against twisted splines.
Remember that no Alli from anyone is gauranteed against twisted splines.
When will you guys learn that you run no faster with defuel eliminated. The nice hard shift is a tie up that locks the wheels for a millisecond. Any firm shift in the Alli is a tie up. First thing that happens is a twisted spline on the planet and C2 hud. 1100.00 before we even touch the truck. Keep the credit cards handy and tune away.
Remember that no Alli from anyone is gauranteed against twisted splines.
When I race the quarter I am looking for ms. in my time, to hell with tenths :rofl:
j/k Mike.
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Here's my experience for what little it's worth...
My LLY had over 500 passes and daily driving. I tried everything in testing in the tcm. Best thing for my tranny was no defuel in the ecm, but keep the defuel in the tcm active. Tranny lived very well like that.
My LBZ is getting in the 300+ 1/4 mile range and this tranny has been in the truck for most of those. No defuel in the ecm tuning(still does it slightly), but I have the torque/rpm management enabled in the tcm. This equates to quick shifts without banging in my case.
With too much defuel on either 11 second truck, the tranny would/will limp. I have never broken a hard part in my tranny and everything lasts a long time. There needs to be balance in ecm and tcm tuning. Just disabling the torque man. in the tcm is not the way to do things.
Of course ecm tuning has a lot to do with how long a tranny will live.
My LLY had over 500 passes and daily driving. I tried everything in testing in the tcm. Best thing for my tranny was no defuel in the ecm, but keep the defuel in the tcm active. Tranny lived very well like that.
My LBZ is getting in the 300+ 1/4 mile range and this tranny has been in the truck for most of those. No defuel in the ecm tuning(still does it slightly), but I have the torque/rpm management enabled in the tcm. This equates to quick shifts without banging in my case.
With too much defuel on either 11 second truck, the tranny would/will limp. I have never broken a hard part in my tranny and everything lasts a long time. There needs to be balance in ecm and tcm tuning. Just disabling the torque man. in the tcm is not the way to do things.
Of course ecm tuning has a lot to do with how long a tranny will live.
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When will you guys learn that you run no faster with defuel eliminated. The nice hard shift is a tie up that locks the wheels for a millisecond. Any firm shift in the Alli is a tie up. First thing that happens is a twisted spline on the planet and C2 hud. 1100.00 before we even touch the truck. Keep the credit cards handy and tune away.
Remember that no Alli from anyone is gauranteed against twisted splines.
I have had this happen on my stock '01 just the other day. just a little tow tune in it and part throttle 2-3 shift, rear tires skidded 5' and then it just kept going. haven't touched the tcm. going back to different OS shifting differently, has anyone had a crappy 01 tcm?
What button are you guys clicking to get no defuel? I've tried all the no tq limit request and rpm limit request buttons I've seen (both ECM and TCM), and I still get a defuel on the shifts. Not that I'm complaining.
GMC_2002_Dmax
The Still Master
TCM Table D5197,
I set mine to all enabled unless it is a built pulling or racing truck, truck then I might set the rpm limit to disable, maybe.............
If you disable the Torque request your ecm will not pull fuel on the shifts, if you would like to create a tie-up that is the best way to do it.
On gassers the ecm pulls timing on the shift to reduce power, we pull fuel to reduce power, also if your trans builder modified things in the VB or fluid routing in the transmission you may have to slow dow some on-coming clutches due to the pressure increases, a hard shift is not the same as a hard TC Lockup.
Just because it feels like a better shift does not mean it is.
When will you guys learn that you run no faster with defuel eliminated. The nice hard shift is a tie up that locks the wheels for a millisecond. Any firm shift in the Alli is a tie up. First thing that happens is a twisted spline on the planet and C2 hud. 1100.00 before we even touch the truck. Keep the credit cards handy and tune away.
Remember that no Alli from anyone is gauranteed against twisted splines.
I agree, I run defuel in all of our trans tunes and the trucks run awesome ETs for the mph that we run. I went 12.37 @ 107 and chris went 12.42 @ 106 - we've both trapped faster but those ETs seem low in relation to the mph when I compare to what others are running. I'd rather make 100 more passes on the trans than shave .01 off my ET.