Seems to be a million options on the market for wiring up your 700r4 to lockup after removing the computer. Been doing some research on this and need a clear answer here:

The pigtail on the outside of the case has three wires. I read somewhere you can take this pigtail, and ground one of the wires, and the other one you wire to a 12v fused switch. Then you flip the switch on when you want lockup in 4th. Then the third wire Im not sure, I guess you leave it alone?

My question being is this accurate information? I realize a lot of people would opt for the kit and have it be done with, but this could buy me some time...Right now Im doing a lot of all around driving, so wiring it as mentioned above and only switching on lockup in 4th will be fine to keep my tranny from burning up? I know its gonna be a pain to rely on a switch, braking could stall the motor, etc, but like I said I just need to buy some time.

By the way its an 87 700r4

 

Depends on your setup. If it's Normally Open or Normally Closed that will affect your wiring. Lockup Switch is fine for limited use, but I wouldn't want to have to deal with constantly for street use. I even ran in non-lockup for awhile. Just too mushy feeling for street use IMO.

Here is my Vacuum Lockup Project done with only spending around $20 total.
https://www.thirdgen.org/forums/carb...up-budget.html

 

Thanks for the info. I researched my options most of the day. What I came out with was fairly simple. Wire 12v + wire (constant power with key on) to a toggle switch, then wire the other lead from the switch to terminal A on the pigtail outside of the case. The other two wires on the trans. case pigtail get spliced together. I used a lighted switch, so the third terminal on the switch goes to ground.

Yes i need to rely on manually switching the trans in and out of lockup, but this configuration does work. I have a tci kit sitting on the kitchen table but it seems too complicated for me to wire correctly.

So as i stand, i can lock my converter up in 2nd 3rd and overdrive. Still have one remaining question however... For in town driving I don't seem to have the need to lock up the converter. On the highway it is definitely beneficial when im in overdrive. Is this basically the just of it? In otherwords, will I be doing any damage operating my lockup switch in this manner? (using it only on the highway in OD) From my understanding lockup is only needed in overdrive on distance drives to keep the trans. from getting into high operating temps. Seeking insight/comments please

 

If you already have a kit bought I would just take it to the local transmission shop if they are decent and pay to put it in. Even if it costs $60-$100 it would be far better than a toggle setup. Safer and less of a chance of messing up a transmission from forgetting to unlock the converter.

Depending on your converter you might not notice the lockup in town. Mine was 2400 RPM spec'd on the normal 350 so it is already flashing higher now. Slipping to close to 3000 RPM as I go through town (3.23 gears) was pretty noticeable. Now it will lockup even around 30 MPH.

I don't know which 4th gear pressure switch you have, but if you wire A to power all the time you will bypass your brake switch. Which can be dangerous if you happen to have to jab the brakes while you're under lockup.

Attached is the diagram I sent the company for my free switch.

 

Cool man. So I only need lockup on the highway?

Intown around here consists of like first gear, 5 mph, stop and go..Maybe in the woods when Im doing a constant 40 in third with noone infront of me Ill hit the switch and it wont feel like its lugging too low.

Just worried about damaging the trans. The car runs really cool anyways, everywhere. Only time it hits 220 is in a drive through. 150-160 everywhere else (ol' trusty gm temp gauge) And I should throw in...The only time I have ever felt excessive 'slipping' is on the highway, doing about 70, with no lockup. This is also the only time Im ever at a constant speed in a constant gear.

So my understanding goes, with my high rear end gears, town im driving it, etc etc, that the lockup is really only needed on the highway. If the computer was hooked up and everything was functioning as it were from the factory, I dont think the lockup would even be kicking in at all with the town driving im doing and trying to explain. Could someone please touch on this? Lockup would only be crucial at a constant speed in a constant gear and not kicking in little or at all if you are constantly changing gears, rpms, and speeds, and lots of times in first gear anyway.

 

Yes to all the above.

I ran mine without lockup for at least 6-7 years with no ill effects; I basically do no extended 4th gear cruising. Then threw in a toggle for a year or so, which I rarely remembered to use. Then formalised it with an automatic circuit, which is lucky if it engages for more than 2 minutes total during my typical 45-60 min commutes.

 

Double post

 

You already have all the supply wiring needed in place.
The stock fused 12 V supply to the trans plug ,through the brake switch that will disconnect the lockup when your foot is on the brake as in the stock setup .

All you do is connect the tan / blk wire from the trans plug (that used to go to the computer ) to ground through your switch.
Do not connect the 3rd blue wire to anything

 

Thanks for the input guys. Ive been going on some open-road test cruises and Im finding the lockup to be beneficial in 2nd and 3rd. It has a lot of extra low end pull with the lockup on. So some questions have surfaced Id like to have resolved:

Say this were a factory setup that hadn't been altered with from the factory..

1. Does lockup ever come on in 2nd and 3rd or only OD?
2. Does lockup stay on during gear changes (up and down) or does it shut off
3. Does lockup come on during WOT or does it shut off (if you were in lockup and went to WOT would it stay on or shut off)


Hopefully someone can answer these questions. Thanks in advance.

 

1.) I'm not for sure but I was thinking it was around 35 mph to 40 mph. So it could happen in 3rd at light throttle.

2.) I would think it would unlock during gear changes to allow slip like a normal manual clutch does.

3.) It should unlock under throttle, braking, and etc.

The reason you don't want it to lockup fully under heavy throttle or WOT is the fact most converters aren't made with a clutchpack to support it due to the added stress. There are some like the vigilante that offer a multiple disk clutch upgrade to allow for it but that's a few hundred extra option.

 

Ok. The TCI kit, for instance, gives directions on how to install their kit, and also how to hook up a switch as an optional. They say for "towing, etc" which made me think of the Tow/haul button on a pickup. Am I on the right path here?

If you were at the strip, would you run button off the entire way down or at any point would you turn the lockup on, or vise versa? Comments please
How would factory lockup react to WOT at dead stop through all four gears. Would it stay off the entire time?

 

Button off. You might see a potential gain on high end but doubt it would be very noticeable.

 

Yes
https://www.thirdgen.org/forums/post...48-post18.html

I know at least one racer who engages the lockup as soon as he engages 2nd gear and claims consistently better ET's from the reduced convertor slippage
Note
He has a aftermarket high stall racing convertor ( that slips more than a stock convertor ) with HD lockup clutch in it

 

Mine is on a toggle swtich. Some say it is a pain but with my cam pulling so low vacuum I need to lock it some how and this is the only way. A lot of times if I am just cruising I will leave it locked so when it goes into 4th gear it immediately locks the converter. Keep in mind when it goes into 4th I am not beating on it with it locking automatically.

BTW I only have 4th gear lockup in my tranny.

 

To add a little more about the question of factory lockup in 3rd, yeah, at light throttle they do lock up in 3rd. Mine still has the factory lockup function and I feel it lock up a lot of times when I'm cruising nice and easy around 35-40 mph.

 

I have mine on a toggle switch, for some reason it doesn't want to lock up on it's own some times. ('7730 ecm, $A1 code with all factory lockup settings).

My converter stalls around 4500, it's handy in town to be able to lock it up whenever. At the track I don't though, tried it but ran slower.

 

I'm just curious...
What's the purpose of this lock up kit? The factory 3rd and 4th lock up is not enough?
Is it for running faster?

 

The majority of us are doing our own lockups due to it no longer being done by the ecm (carb swap).

 

[QUOTE=fireturd350;5567942]The majority of us are doing our own lockups due to it no longer being done by the ecm (carb swap).[/QUOTE

Now I've got the point. Thank you

 

Hey brother,

am there with you. I just lost 3 and 4 on my 700. Did a good job stock for 13 years after I put a zz4 in front. I do have a toggle switch that shuts down the TCC in the first three. Overdrive always overrides the switch so I have TCC in overdrive. But since I rarely post,,,, when available funds come my way,,,how are those vigilante converters doing on this board?

 

90 IROC TPI with mods running low 13's. I engage lockup in second at the strip and pickup a tenth thru the quarter. Also daily driving, I pickup about 2 mpg with lockup.

 

Go on you tube and listen to what Lou Koulouvaris has to say. I'm not even going to hook mine up.

 

It's a 2 min video

 

Oh No! Zombie post from 2013! Shoot for the head!

 

Hi, I'm trYing to figure out which one is the terminal A? Any help appreciated.
thank you

 

Hi, Can you please tell me what terminal A Is?
Mine is 1989 700r4 transmission

 

http://lmgtfy.com/?q=700R4+TCC+pinout+terminal+A

Click on the images tab.....

GD

 

Terminal "A" is part of the connector on the passenger side of the transmission case. It is part of the electronic controls for the transmission.

Terminal "A" does different things depending on the model/type of 700R4 transmission you have. In '87, there were 15 or so different types of 700R4 transmissions.

Terminal "A" is connected to either:

1. The 4-3 downshift switch.
2. The positive side of the TCC solenoid.
3. 4th clutch switch.
4. 3rd clutch switch.

 

Not likely to hurt trans by having lockup stuck on.....in fact later cars lock up converter in trans limp mode to save it.....js

 

Lot of info here.

Any chance i could get a question answered?
I got a 92 700r4 put in an 84, no comp
Im going to put in a lock up because it will be a daily car.
IS there any lock up kits that will make it work with the stock shifter?
And if not, i want to go with something that does it automatically, like one of the kits with a little comp on its own.

 

Yes, if you are interested in a kit I would reccomend the TCI lockup kit. I think its about $100 and after installed will lockup automatically when needed.

 

Hey there, im trying to do this wire up, can you give a little more detail please? Im looking at the wire diagram and it goes from the gauge fuse [10A] to the brake switch, to the trans, out to tan/black wire to the ECM.
my wires a bit of a mess, any idea how i can locate the tan wire and where exactly in that circlet do i tap in for the 12v to power the new plug? for the TCI lockup. I already have the pan harness done, just trying to get the 12vs to power it. Everytime i tryed to run it from the pink/black wire i kept blowing the gauge fuse. Any tips???