Shift Firmness vs. Line Pressure

[dantwomey]

I am borrowing some opinions from a thread on LS1Tech titled, Line Pressure Discussion (when is too much) to start some discussion here.

 

I'm interested in line pressure because I've read it directly controls shift firmness. Now since I've also read that when you install a stall converter your shifts soften alittle I'm interested in tuning my line pressure to control this softening.

 

According to some of the posts in the aforementioned thread the factory spec for line pressure is 189lbs. They also state that most vehicles are delivered in the 170-180lbs range. Further discussion in this thread seems to indicate that we can safely run up to 210-220lbs of line pressure.

 

My tranny shop claims to have the appropriate guages so when they install my TB TC in the near future I'm going to take them up on their offer and have them 'tune' me for maximum shift firmness.

 

Does anyone else have anything to offer here?

 

Regards,

Dan

[zippy]

without a doubt if they have the tools to do this you can greatly benefit from it. doing so is alot like datalogging the engine. most of your big performance type transmission shops do this same thing except through the use of a transmission dyno. i say go for it. you'll likely be very happy with the results. to do this properly though, you're going to want to use a tuning software such as hptuners or something similar. using a tuning software you can make changes to the pressure depending on torque output of the engine, engine temperature, trans temperature, base pressure, shift time compensation, etc. almost all of the pressure adjustments to the 4L60/65/70E need to be done through the computer programming rather than internally.