APPS Lockup voltage needed

BgBlDodge

BgBlDodge

Hates hippies
Joined
May 7, 2007
Messages
16,647
Anyone know what voltage it takes to signal the PCM to lock up the converter and to engage OD as well? Trying to get this POT dialed in on my conversion but I'm having some difficulty. Figure that if I can dial in the voltage and then fine tune from there I'd be light years ahead instead of driving around and stopping and adjusting it. Thanks.
 
doesnt really work like that. pcm factors in throttle %, engine load, wheel speed, rpm and probably more.

you should be seeing 3.5v at WOT and .3-.6v at idle
 
Hmm. Maybe set it for 3.5v so it thinks it's ready for lockup in 3rd and 4th?
 
I'm running a p-pump on my truck now and instead of paying $200 for a 12v TPS I'm using a potentiometer instead. It's a popular mod on the 12v's to replace the TPS completely with a POT. Now I see no reason why doing that on a p-pumped 24v with a 47re would be any different than doing it on a 12v with a 47re. Just a matter of dialing in the voltage just like the 12v for lockup and OD.
 
BgBlDodge said:
I'm running a p-pump on my truck now and instead of paying $200 for a 12v TPS I'm using a potentiometer instead. It's a popular mod on the 12v's to replace the TPS completely with a POT. Now I see no reason why doing that on a p-pumped 24v with a 47re would be any different than doing it on a 12v with a 47re. Just a matter of dialing in the voltage just like the 12v for lockup and OD.
Click to expand...

i think you missed the point of the mod. you cant just set it to one voltage. the PCM needs to see what throttle % you are at to adjust shift points and line pressure, as well as TC control.

you need a sliding pot that is set up as a TPS to tell the pcm what % the throttle is at, so you need it to go from .3-.6 at idle, and 3.5v at WOT
 
Rollin Coal said:
i think you missed the point of the mod. you cant just set it to one voltage. the PCM needs to see what throttle % you are at to adjust shift points and line pressure, as well as TC control.

you need a sliding pot that is set up as a TPS to tell the pcm what % the throttle is at, so you need it to go from .3-.6 at idle, and 3.5v at WOT
Click to expand...

x2.

This is why I always express concern in every pot mod thread I've seen. It isn't as clear cut as most seem to think it is.

If you want to try running a pot, just mess with it until you get it to do what you want. It isn't rocket science.
 
On the 12v's the POT can either be mounted in the dash or left hanging in the engine bay. It's not connected to the throttle at all. It's a 5k linear taper POT.

Now, this is how it works on the 12v. The 24v might be different and that's what I'm running in to but I figured I'd try and give this a shot first and see if it works.
 
BgBlDodge said:
On the 12v's the POT can either be mounted in the dash or left hanging in the engine bay. It's not connected to the throttle at all. It's a 5k linear taper POT.

Now, this is how it works on the 12v. The 24v might be different and that's what I'm running in to but I figured I'd try and give this a shot first and see if it works.
Click to expand...

I know what it is and how it works. I primarily work on 12 valves.

The problem I see with it is just as Rollin Coal described. The RE transmission has a governor solenoid and pressure transducer so that the PCM can control all the shift points. By using a pot instead of a TPS you are taking some of its control away and it won't be as effective as it was before.

Some people seem to like it, but I personally don't think it is a wise idea. Like I said before, if you really want to run a pot, just hook it up and adjust it to your liking. Each setup is different, so there is no way a person can tell you where the voltage needs to be for your given application. Even switching tire size can create a need to adjust them.
 
You must log in or register to reply here.
Back
Top