BSiegPaint

I'm almost finished with the installation of my 200-4R. Wiring is the only holdup at the moment. I have found plenty of web sites with instructions on how to do this, but nothing with the level of detail I need. I've searched here and only found similar "generic" instructions - not being an electrical guy, I need more help than what I found.

I used this web site and instructions for my starting point: http://www.73-87.com/7387garage/drivetrain/lockup.htm

Several of the part numbers have been superseded and I was able to get the current parts. The GM vacuum switch is discontinued (but a few are available for $90 plus shipping ) so I found a "universal" adjustable vacuum switch that looks like it should work.

So here's what I've done - changed the 4th gear switch to a normally open/pressure closed single pole switch (GM #8683502). The negative wire from the solenoid runs to it. The positive wire from the solenoid now runs to a single pole connector on the side of the transmission. I now need to get switched power to the transmission.

I have a replacement brake/cruise control switch that everyone says will work. Problem is, I don't know how to wire it up! Does it already have power going to it from the brake wiring (orange and white wires)? Or do I need to run 12V to it and ground the other tab? Does it matter which pin I use for ground and for 12V? Or can I just hook up a wire to either connector tab and run it to the vacuum switch?

Once I figure out power to the brake/cruise switch, I want to use the vacuum switch to delay 4th lockup. So power has to go from the brake/cruise switch to the vacuum switch, pictured below. The instructions with the switch are completely inadequate, and I'm not sure which connections to use here - maybe someone has seen this switch, or recognizes the little schematic on the side? From the vacuum switch, I will run to the 12V connector on the side of the trans. Sound right?

So here are the two switches I have. On the brake switch, the left two tabs are my concern - how do I connect these?



I'm just confused as to which tabs need which wires going to them. I don't have a bench to test a circuit, but maybe I need to put one together in some manner. I'm thinking that 12V needs to go to the top tab on the vac switch from the brake switch, then 12V from the middle tab to the trans, with the bottom tab going to ground. Thoughts?

At the very least, I'd like to get the brake switch hooked up. With power to the trans, I'll at least get 4th lockup in 4th, though not delayed, so at worst the trans will WORK, and I'll figure out the vacuum switch later. The biggest concern is the brake switch, so any and all help is appreciated!!!!

7T1vette

Are you just trying to wire in the lockup function? If so, you just need a "Normally Open, Momentary Close" switch to activate it (get power to the circuit) and connect the 'drop' switch [at the brake pedal] in that 12vdc line before it reaches your 'set' switch. Your switch and wiring need to be able to supply the current required by the lockup system; or you need to put a power relay in your hookup, also. I believe that the standard cruise switch (or part of it, anyway) is a NOMC switch, so that would work if wired properly; but it might be easier to get a little lighted (12vdc) panel-mount push-button NOMC switch at Radio Shack to mount to the side of the tranny tunnel (or other accessible location). Several aftermarket suppliers sell a 'controller' box for doing just what you are attempting. Check to see if lectriclimited.com offers one.

Artsvette73

You could have just run a relay off the brake sw. The vacumn switch does not delay the lockup at all. It will release the lockup when you nail the throttle

CA-Legal-Vette

At least then you won't have the lockup on at idle. It will, however, come on in any gear at part throttle or more.

BSiegPaint

I actually have a vacuum delay in front of the electric vacuum switch, so the lockup will be delayed. It has no electric hookup, so I left out mentioning it here. And I want the lockup to release when I nail the throttle, rather than having to tap the brakes, flip a switch or downshift first.

CA-Legal, only 4th gear is hooked up to the lockup switch - 3rd is bypassed with the new internal wiring. I'll only lock in 4th.

7T1 - your post repeats most of what my original post says. What I need to know is how to wire the brake/cruise switch - there are two terminals on the switch - is one a ground and one 12V? Maybe the brake wires that are connected to it provide power to it? There are no markings. Everyone says to use this switch, but I can't find anywhere that actually tells how to hook it up.

MakoShark72

This is great timing...I have my 2004R installed in my 72, and am clueless as to the wiring. There is a single wire on the transmission, thats all.. The transmission shop told me that I just need a manual switch, he said nothing of a brake pedal-actuated vacuum switch.

I think I would prefer not to use a manual lockup switch. The vacuum switch sounds better to me...

I need to get this figured out as I am almost ready to drive after 3+ years..

Any and all help is much appreciated!!!

Rob

BSiegPaint

OK, I'm going to scan a rough diagram of what I think the wiring should look like. If someone can look at it and comment/troubleshoot, it would be appreciated. I found a little more info on the brake/cruise switch online, and it appears that 12V should go to one tab and the other should connect to the circuit - and it doesn't matter which goes to which. Hang on and I'll see if I can get my scanner going...

Mako, if this all works, I'll post up the whole thing. If someone has done this like I'm doing it, they haven't posted about it anywhere. I'm combining info I've received from 7 or 8 different sites.

BSiegPaint

OK - here's a ROUGH drawing of the way I intend to wire this thing. Technically, if I can't figure out the vacuum switch, I could bypass it entirely and just wire straight from the fuse box ACC 12V to one tab of the brake switch, then from the other tab straight to the tranny, right?

MakoShark72

What is the "vacuum delay" in your drawing??

Also, I guess my question is... does the 2004R ONLY lockup in 4th??? I know, I'm clueless!! Never understood the whole auto trans thing anyway...

Thanks,
Rob

BSiegPaint

Mako - it's a Borg-Warner EC342 vacuum delay valve. It slows the vacuum build so that you get a slower shift into lockup. I didn't want to lockup immediately when shifting into 4th. Lots of cars used to use GM # 14020691, but it's been discontinued. I may not need to use it - I just have it in case I don't like the upshift I get without it. Look back to my first post and click the link. It doesn't show well, but when the wiring is reconfigured inside the trans, the 3rd lockup switch is bypassed, so this will only lock in 4th. I hope this all works...

BSiegPaint

Well, no recent replies (I know it's the middle of the day and normal people are working, lol) but I've got to get moving on this. So I'm going with the diagram I have above, and I'll let you know if it works...

Artsvette73

I used the BTO wiring diagram. If you have a 2 wire solinoid just ground the black wire. The pressure sw. is GM # 8643710 N.O. The GM vac. sw. is 14014519 sill active on GM parts direct.

http://www.700r4.com/tech/tcc/relay_.../diagram.shtml

BSiegPaint

Thanks, Art, but while I have a two-wire solenoid, I have a single post pressure switch. BTO uses a two-post switch. And the vacuum switch still shows as current on the GM Partsdirect site, but ordering it gives you a backorder. There are only a handful of these switches left in the US (I have the list of locations) and it's almost $90

While I appreciate the schematics and such, I'm looking for something as simple as the drawing I have above. This wire goes to this tab, this wire goes here, etc. I have just finished installing the wiring as I have drawn above. The only thing I'm lacking now is a ground for my driver's side vaccum switch on the firewall.

Artsvette73

The Vac. switch should run in series with the 12v power source like in your schematic. I am confused why you would want to ground it. That would be a dead short.

mrvette

Do NOT ground anything off that pressure switch....

in fact you do not need it at all, really.....

the tranny will lock only in 4th gear then....

the brake switch as shown is fine....just run the wire to the tranny instead of the vac sw as shown....

you CAN use the vac switch that way, but fail to see it will do anything except drop the lockup if you really hit it in 4th gear, I fail to see the point in a car as light as the vette....

IF I was to do the vac switch it would put it in parallel with the 4th gear lockup point inside the tranny, in which case the ground to the vac sw is needed, and the other side is connected to the tranny....BTW, there are some selection options of 4th gear lockup switches at various pressures which will change your speed as to when lockup occurs....

I dunno which is considered normally open (NO) or normally closed (NC) as marked on the vac switch, so you need experiment with it....

BSiegPaint

Thanks everyone! There is a bad schematic that came with the vacuum switch that showed the third tab going to ground and the middle tab being used for nothing at all. That's the reason for my ground. I'll get rid of the ground. Take a look at the picture of the black switch above - it shows a little diagram on the side. It makes me think that running it as a parallel switch would cause me to use the bottom and top tab, and not the center (sort of like the bad instructions show).

Thanks again for your time and comments - I am feeling better and better about the project. I got it all buttoned up tonight, and with a coolant fill and trans top-off, I hope to get it started tomorrow. Cross your fingers.

redwingvette

I would remove the vacuum switch and use a toggle switch.
Here is how I wired mine when I first put it in.

Later I took out the toggle switch and replaced it with a B&M controller.

Now the converter engages/disengages using the speedo cable and I have it set for 40mph. Above 40 it locks, below 38mph it unlocks.

BSiegPaint

Redwing - Thanks for the input. I've looked at the B&M controller as well. Just a little spendy for me at the moment, but might be the best option overall. The vacuum switch should do for me what a toggle would do, but the jury is still out. I don't want to think about the operation of the transmission while I'm driving. It's an adjustable switch, so I can change the level of vacuum at which it locks the converter in 4th gear. I'd rather it not lock until I'm cruising with a steady vacuum... Getting into it with my foot a bit should unlock it right away no matter the speed. Hope to know something today if the new motor fires up without a hitch...

'75

The adjustable vacuum switch looks like a good idea, what is the part no and source for it?

tarheeljww

Very Informative thread.....

The 200r4 is my next project, and I have been talking to a shop, Transmission Depot, as I found them on e-bay, and they are only an hour from me.......

They say they will install the 200r4 with a carb kickdown.......and if I understand them correctly, I won't need any wiring or computer......

Can anyone shed any light on this, and could this be a solution for the OP...?????