8.1 Allison tuning

[superwagon]

I am sorry if this been addressed previously. I have a customer with a 2002 silverado with 8.1 allison and I used the other software to tune his truck before I purchased efilive. When I tried to adjust for his oversize tires things didn't work? Can I license just his allison and adjust for tire size ,torque management, shift speeds etc. with efilive? If I can license just the allison how much will it cost? Like I said I am sorry if this stuff has been addressed in previous posts but I can not seem to find real answers involving this 8.1 allison combination. I have emails stating that the other software did support this but now I am told that they don't by the very same person? Very frustrated with the support by the other software!
Thanks!
Doug

[rcr1978]

If you have tuned any other vehicles and not the transmission you will have spare transmission licenses, or if you have unused licenses at all you can use one of the trans slots for one of them but you will be short one but will still be able to tune a ecm then that license will be used up. I guess if that doesn't explain things think of it this way, every license you buy from efilive will be able to tune one ecm and one tcm, so if you don't use both the ecm and tcm on one vehicle you will have a spare controler left but one license will only work on one ecm and one tcm.

[THEFERMANATOR]

You can license just the TCM, but why do you think you need to adjust the TCM? ALLISON tuning is NOTHING like tuning other GM trannies. Unless you have some specific reason to change shift points, then there is no reason to. The ALLISON coudl care less what tire size or gears are in it, it will shift at the same driveshaft speed regardless of what gears or tires are on it. And adjusting it is NOTHING liek adjusting the GM PCM's. They are calibrated for 4.10 gears and 245/75/16 tires regardless of what gears and tires it has in it, and the shift speeds in the tables will not match actual speeds unless it happens to have 4.10's and 245/75/16 tires. And torque management and such is primarily controlled in the ECM for diesels, I would assume the 8.1L is the same way.

[superwagon]

Thanks for the help guys. I understand that Allison is nothing like a 4l80e. My main problem with this trick is recalibration of the speedometer for his oversize tires. My customer has been doing his own research on torque management and would like it to be reduced in the transmission side. From what I have researched any torque management requested by the tcm is going to be handled by the ecm thru timing reduction. So I ultimately do have control over transmission torque management thru the ecm in the end.

[THEFERMANATOR]

Thanks for the help guys. I understand that Allison is nothing like a 4l80e. My main problem with this trick is recalibration of the speedometer for his oversize tires. My customer has been doing his own research on torque management and would like it to be reduced in the transmission side. From what I have researched any torque management requested by the tcm is going to be handled by the ecm thru timing reduction. So I ultimately do have control over transmission torque management thru the ecm in the end.

Both of which are controlled via the ECM, NOT the TCM. Do NOT mess with the TCM's speedo settings as it will change it's adaptives, grade braking, shift points, and so on and son in BAD ways. We see less than 1% of what is i nthe TCM programming with EFILIVE, and some of what we have should NOT be messed with. The speedo settings are 100% controlled by the ECM and it's outputs, changing the TCM's settings will only result is messing up all of the shift points and possibly disabling grade braking and other features. As for torque reduction, have you tried changing the torque tables in the ECM yet?

[superwagon]

My customer drove a truck tuned by bb performance and was told it was stronger running because he could adjust TM thru the tcm and that is where most of the tm is on these.

[THEFERMANATOR]

There is a table for desired torque request in the TCM, but it is a hypothetical chart. I haven't ever tuned an 8.1L/ALLISON combo, but I know with the DURAMAX some have adjusted the TCM for it, but the best way is to adjust the ECM since it controls the fuel and how it handles the request. The 8.1L could be different, and I can't tell you for certain.

Heres a thread I found when searching for torque management on the 8.1L. http://forum.efilive.com/showthread....p-with-my-8-1L

[superwagon]

Thank you for your help Thefermanator! I will look over that thread tonight.