700r4 Electrical Questions

[patmckinneyracing]

Alright this is what I'm trying to do. I'm making an electrical setup to control the lockup on my 700r4. This guy's website is what I'm using as a reference since he basically made a copycat setup of the Painless Wiring Harness using stock components: http://www.73-87.com/7387garage/drivetrain/lockup.htm

Two questions: Are the pressure switches in stock 700r4's typically open switches or closed switches? Where the hell is the low vacuum switch? I searched all over the place in the yards for it but I didn't know exactly where to look for it. Any help is appreciated.

 

[84e/c]

hope this helps some. my guess is open.
http://www.tciauto.com/Products/Instruc ... 0_inst.htm

 

[tc1959]

Alright this is what I'm trying to do. I'm making an electrical setup to control the lockup on my 700r4. This guy's website is what I'm using as a reference since he basically made a copycat setup of the Painless Wiring Harness using stock components: http://www.73-87.com/7387garage/drivetrain/lockup.htm

Two questions: Are the pressure switches in stock 700r4's typically open switches or closed switches? Where the hell is the low vacuum switch? I searched all over the place in the yards for it but I didn't know exactly where to look for it. Any help is appreciated.

It's screwed to the firewall on 80s Chevy & GMC trucks

 

[84cutspreme]

Okay my insight....

1st there is no vacuum on the 700r-4, or at least not on any of the ones I've worked on and built. (Maybe on early model or truck trans, mine all came from camaros)

How do you want TC to lock-up? The TC always locks up electrically, either wired to a switch(manual lock-up), wired to 4th gear pressure switch(which will lock-up only in OD) and lastly the stock setup where it will lock-up in almost any gear(I have never seen it lock-up in 1st but I do believe it's possible)

If you have any more questions I would be glad to help. I rebuilt my 84' 700r-4 and wired the lock-up to 4th gear pressure switch and have it lock-up in OD really just for highway mileage

 

[tc1959]

Okay my insight....

1st there is no vacuum on the 700r-4, or at least not on any of the ones I've worked on and built. (Maybe on early model or truck trans, mine all came from camaros)

How do you want TC to lock-up? The TC always locks up electrically, either wired to a switch(manual lock-up), wired to 4th gear pressure switch(which will lock-up only in OD) and lastly the stock setup where it will lock-up in almost any gear(I have never seen it lock-up in 1st but I do believe it's possible)

If you have any more questions I would be glad to help. I rebuilt my 84' 700r-4 and wired the lock-up to 4th gear pressure switch and have it lock-up in OD really just for highway mileage

The vacuum switch is a vac/electric switch that controls when the TCC can lock up. My painless wiring kit had one.
In the pic attached to This you can see it attached to my brake line It has a vacuum hose and a electrical connector. It keeps the TCC from Applying too soon .

 

[patmckinneyracing]

I found the vacuum switch at the yard. The vacuum switch uses vacuum to send an electrical signal to the trans when to unlock and lock. I had to look at early trucks that first came with the 700r4 in order to find it. Now I'm trying to figure out how to get the 4th gear pressure switch out of a donor valve body. Channel locks?

 

[tc1959]

I found the vacuum switch at the yard. The vacuum switch uses vacuum to send an electrical signal to the trans when to unlock and lock. I had to look at early trucks that first came with the 700r4 in order to find it. Now I'm trying to figure out how to get the 4th gear pressure switch out of a donor valve body. Channel locks?

Oil pressure switch socket. or a box end wrench.channel locks would probably work just be careful.

 

[patmckinneyracing]

Do you guys know if I need the 4-3 "sputter?" switch? It's located next to the 4th gear pressure switch and is meant to soften the shift when you downshift from 4-3. Supposedly without it, the downshift is very rough and doesn't feel good at all.

 

[patmckinneyracing]

Ok guys here is an update. Went to te yard and got all the pressure switches and wiring. The question I have is concerning is with the pressure switches. Of course there is the 4th gear pressure switch (farthest left), next to it with yellow tabs is the 4-3 sputter switch?, but I don't know what the one next to the 4-3 switch is, and then there is another one on the far right that was located right next to the solenoid and I have no idea what it is either. Anyone know what these two switches are?