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View Full Version : What is the best way to firm up shifts?



Redline Motorsports
November 13th, 2005, 02:36 PM
What is the best way to firm up the shifts without killing the tranny? Also will firming up the shifts help cleanup some of the "loosness" you get with a converter change?

Thanks

Howard

wait4me
November 13th, 2005, 04:15 PM
Im up, just call me.

Chris81
November 14th, 2005, 02:06 AM
I would like to know as well.. i've heard many different things.

Texas Terminator
November 14th, 2005, 05:12 PM
What is the best way to firm up the shifts without killing the tranny? Also will firming up the shifts help cleanup some of the "loosness" you get with a converter change?

Thanks

Howard

the "looseness" of a converter will never go away, it is just how a higher stall converter works, by slipping. you may want to start by eliminating your TQM first before you start messing with the tranny. from my previous experience with changes to the tranny firmness in the ECM, you will get a minimal improvement. if you want to do it right, have a REPUTABLE place put a kit in it. JMO.

Redline Motorsports
November 15th, 2005, 04:07 PM
What is the best way to firm up the shifts without killing the tranny? Also will firming up the shifts help cleanup some of the "loosness" you get with a converter change?

Thanks

Howard

the "looseness" of a converter will never go away, it is just how a higher stall converter works, by slipping. you may want to start by eliminating your TQM first before you start messing with the tranny. from my previous experience with changes to the tranny firmness in the ECM, you will get a minimal improvement. if you want to do it right, have a REPUTABLE place put a kit in it. JMO.


Yeah I know that the converter will always loosen up the feel. I just was wondering if certain parameters could possibly firm it up some.

I thought that the trans. shift kits where problems when trying to tune the transmission?

Texas Terminator
November 15th, 2005, 05:26 PM
you can always turn up your line pressures a bit, but, like i said, the gains will be minimal. and no, you won't have any problems with an aftermarket shift kit as long as you use a REPUTABLE installer. the biggest thing that a "shift kit" does is really just let the tranny shift quicker and firmer with larger orifices. basically allows the tranny fluid to flow quicker to the servos, clutches, etc. another thing you can do if your converter is a lock up, you can set it to lock up a little sooner in 3rd and 4th. you could also do 2nd but i wouldn't.

ToplessTexan
November 16th, 2005, 01:53 AM
Howard, one strategy you might use if you're working with lower gearing as well would be to upshift sooner at lower TPS. Lots of folks seem to like this as it sort of masks large converter effects (e.g. increased exhaust noise) in the "just cruising around town" mode. Increasing shift firmness won't change perceived "looseness" too much. That's a function of shift extension as much as anything else. There's just not a whole lot of change in engine speed at low to intermediate throttle upshifts with biger converters. You can make the shifts quite harsh and still have a what feels like sloppy throttle.

Redline Motorsports
November 18th, 2005, 12:52 PM
Howard, one strategy you might use if you're working with lower gearing as well would be to upshift sooner at lower TPS. Lots of folks seem to like this as it sort of masks large converter effects (e.g. increased exhaust noise) in the "just cruising around town" mode. Increasing shift firmness won't change perceived "looseness" too much. That's a function of shift extension as much as anything else. There's just not a whole lot of change in engine speed at low to intermediate throttle upshifts with biger converters. You can make the shifts quite harsh and still have a what feels like sloppy throttle.

I agree. Its a H2 Hummer that we did a H/C setup to. The customer decided at the time to use a 2500 stall converter and its just too much. With such a heavy truck and the additional power, the truck is stalling way to high. We are yanking it out and putting in a 700 over stock unit that should bring the tranny shifts back quite a bit.

As soon as we make the switch, I am going to screw with some of the shift parameters!

Thanks

HT