Allison line pressure

LMM_Austin

Member
Oct 31, 2015
43
0
6
New York
Hey guys looking to get some info on line pressure. Truck has built engine and trans with gorend j extreme disc, mike l trim springs, cut converter flow valve, 2 shims and spring. Truck should be about 1200hp and sees very few street miles. Now let's talk line pressure at idle pressure is about 200-210 at 1500 rpm 360 and 3500 about 380. This seems too high for any application but I also don't build these every day. The trans shifts perfect other than the pressure but I do have a problem with the converter only stalling at about 2200-2300 trying to make boost off the line which is odd because normal driving it seems to be between that 2700-3000 stall. Thanks guys for the help.
 

TheBac

Why do I keep doing this?
Staff member
Apr 19, 2008
15,300
1,596
113
Mid Michigan
Which trans? Early 5 speed? LBZ/LMM 6 speed? LML or L5P 6 speed? Who built it? Which kit was used?
 

JoshH

Daggum farm truck
Staff member
Vendor/Sponsor
Feb 14, 2007
13,588
611
113
Texas!!!
Are you pushing through the brakes at 2200-2300 RPM, or does the engine just stall there?
 

Chevy1925

don't know sh!t about IFS
Staff member
Oct 21, 2009
21,106
4,841
113
Phoenix Az
what color pressure spring? seems about right for the 2 shims and i think orange or red spring on pressures. thats what mine ran at.

line pressure shouldnt affect your converter stall speed that i am aware of. you sure its a J in there? how many miles on it and the trans?
 

PureHybrid

Isuzu Shakes IT
Feb 15, 2012
3,308
350
83
Central OH
It is the orange spring just seems a little high to me. But yes it is a j extreme disc only about 300 miles on it

You have an aftermarket spring with 2 shims, and a modded converter valve. How much do you think it should have? Remember stock is over 200, and this isn't a 47/48 Chrysler trans