PDA

View Full Version : How to tune / protect Allison



Boost
January 28th, 2007, 01:25 AM
I am starting to figure out how to make some decent gains with my LBZ. I want to protect the transmission from the extra power I'm making. Do I raise the line pressures? I don't mind sacrificing some performance on shifts if it allows me to run better with very high horsepower and torque. Are there any changes I should make to the tranny that would actually help performance without breaking it? Thanks you.

JakeGMCHD
January 28th, 2007, 02:32 AM
You could install the Transgo Jr. kit. After that you will need a converter. When decide to upgrade your converter install a pump to raise line pressure. Might as well install some better clutches.

Boost
January 28th, 2007, 07:13 PM
Thanks. Can't I just raise line pressures through EFILive? I was referring more to protecting the Ally through tuning with EFILive if that's possible *I'm sure it is to some degree).

lakingslayer
January 29th, 2007, 09:26 AM
There is no way to tune EFILive to make the trans work better with power beyond it's capabilities. The line pressure can only be raised by changing transmission hard parts. The best way to protect it is to get a good trans kit from either Suncoast or ATS and do it right.

Boost
February 1st, 2007, 01:52 PM
Thanks for answering, but I'm still a bit confused.... how come I can adjust the line pressures on a 4L60 & 4L80? Is it only the Allison that you can't adjust line pressures on?

Kennedy Diesel
February 2nd, 2007, 04:42 AM
The Allison main psi is analog. Just a valve and spring...

Boost
February 2nd, 2007, 12:06 PM
So I take it that means it's not adjustable "electronically". Sort of like running off the wastegate spring only. So what are we going to tune on the Ally when 6spd support comes out??

Whippled 496
February 3rd, 2007, 05:13 PM
I am finding other than reducing torque management, that the Allison is pretty spot on as far as shifting is concerned. Reducing TM really made a big difference in the feel of the Allison. TCC lockup adjustment or shift timing may make a difference too, but I have not messed with those at all yet.

Boost
February 4th, 2007, 02:00 AM
However, reducing TM will hurt the tranny more. I am interested in protecting it somehow, since I'm making more power. I am sure that reducing TM improves performance unless there is too much slip, but I am really impressed with the way a stock Ally handles 500 hp / 1000 tq, and I don't want to ask it for too much. When I can afford a fortified tranny, I will make it shift very hard.

DURAtotheMAX
February 6th, 2007, 04:02 AM
Thanks. Can't I just raise line pressures through EFILive? I was referring more to protecting the Ally through tuning with EFILive if that's possible *I'm sure it is to some degree).

nope. The allison is 110% different in terms of design and operation to a 4L60/4L80.

Its NOTHING like any other automatic out there, conventional trans methods and mods do not apply. You need to go inside it to get it to hold any additional power.

The stock allison will NOT handle 500hp/1000ft lbs of torque, I can tell you that right now :)

ben

Boost
February 6th, 2007, 03:23 PM
Thanks for the info. So what is the point of tuning the Allison then?
Also, I don't want to jinx myself, but I have 21k miles on a very well maintained 100% stock 6spd Ally, and I am running 500+ hp and 900+ tq daily.
Am I just luck? Will it fail soon?

trudynosports
February 11th, 2007, 09:27 AM
Yes, your very lucky and on borrowed time!

Whippled 496
February 11th, 2007, 01:13 PM
Thanks for the info. So what is the point of tuning the Allison then?
Also, I don't want to jinx myself, but I have 21k miles on a very well maintained 100% stock 6spd Ally, and I am running 500+ hp and 900+ tq daily.
Am I just luck? Will it fail soon?


are those figures at the rear wheel? 500/900 at the rear wheel is pretty steep. They say the allison can handle the HP better than it can the TQ, but i dont really know. I am 400hp/500tq at the rear wheel with slightly reduced TM and have noticed no issues. Its been this way for about a year now. I drive it about 1 day a week and baby the hell out of it unless someone provokes me, I also go to the track with it about 10 times a year.

Boost
February 11th, 2007, 02:22 PM
I dynoed 421 hp and 635 torque to the wheel with a program that is inferior to the one I'm running now. According to my calcucations (20% drivetrain loss through the Ally) that equals exactly 527 hp and 795 tq. Can't get this stock tranny to show any signs of failure yet at 22k miles. Will let you guys know.

Extinct
February 11th, 2007, 05:02 PM
I dynoed 421 hp and 635 torque to the wheel with a program that is inferior to the one I'm running now. According to my calcucations (20% drivetrain loss through the Ally) that equals exactly 527 hp and 795 tq. Can't get this stock tranny to show any signs of failure yet at 22k miles. Will let you guys know.

Feel like sharing that tune ?

lakingslayer
February 13th, 2007, 01:26 PM
It's only about 14% drivetrain loss through a solid allison (built up). Usually the Max Torque is about twice the number that the Max HP is. Check my dyno numbers. They both happen at differernt RPM's where the Max TQ is at a lower RPM than the Max HP.

Boost
February 13th, 2007, 02:34 PM
Feel like sharing THAT tune? :wave:

lakingslayer
February 14th, 2007, 02:39 AM
Feel like sharing THAT tune? :wave:
Sorry!