Michel B

Hello

I'm going to install the 200r4 this weekend,, studieing the wiring diagrams from Bowtie it seems rather simple. I thought of purchasing there kits but found them rather expensive for a had full of wires and connectors that I have readily available at home. I do have a couple questions,, maybe someone can help me out here.

http://www.700r4.com/tech/tcc/index.shtml

Keeping this simple
In the brake switch method,, is the 4th gear switch fed hot (12v) at all times to in turn send voltage to the solenoid when in 4th,,, then when brakes are applied the power is cut and lockup canceled.

Any suggestions welcome

TimAT

Power is on to the brake switch which is closed (brake not applied) then to the 4th gear switch in the trans (normally open) then to the TCC. When it shifts to 4th, the switch closes and the TCC locks. Touch the brake and the brake switch opens kills the power.

Your thoughts are correct. I'd also think about the possiblility of adding a vacuum switch too- that way a slight increase in throttle wll dump the lockup, which adds the torque multiplication of the convertor back in and will hold it in 4th (not locked). May improve the feel a little. As it is in the diagram, as soon as it hits 4th the TCC locks- basically 2 shifts at the same time. Might feel a bump when that happens.

redwingvette

Adding a vacuum switch is a good idea. I had some extra cash so I installed a B&M controller instead. Now my convertor locks only if I am going over 40mph.

Michel B

The vacuum switch sounds like a good idea,, if I understand this correctly, once the lock up is ingaged in forth gear it stays locked unless the brake switch is applied,,ok,,, what happens when the gears drop and no braking is applied ?? Is this where the vacuum switch comes in ?? Also,, does it come into play when kick down is applied ?:o

Bee Jay

Wow, you would need some extra cash for that. I have a $5 switch on my console to lock up manually. The brake pedal will still disconnect. I find that I use the lockup very rarely because I'm rarely on the interstate, and even then, when I give it a little gas or a lot of gas, the response with lockup not engaged is much mo betta. At light load highway speeds, the converter isn't slipping that much. The B&M controller is speed activated, I wonder if anyone has used an rpm activated switch. I wouldn't want lockup at anything under 2000 rpm. My previous 700R4 only locked up in 4th.
Bee Jay

Michel B

So you wired your switch to cut all voltage to the 4th gear switch when not wanted ??

Theiskell

Bee Jay,
This is something I would like to wire in on my 200r4. Do you have a diagram of how you wired the switch? I think this would solve my problem of lugging at lower speeds. If I am understanding you correctly you wired a switch that keeps the converter from locking in until you manually flip the switch then it operates normally….am I correct???

redwingvette

I did the $5 toggle switch before I went to the B&M controller. The B&M controller makes it completely hands-free and if wired correctlly iwll lock the convertor in any gear , like 3rd, as long as you are going faster then the setpoint.

Bee Jay

That is about how mine is wired now. the same hot that goes thru the brake (I used a cruise control brake switch) goes thru my toggle on my console. I leave the switch off most of the time. If I find myself on the highway cruising I switch the lockup switch on. Whenever I hit the brakes, the power is interupted. My previous 700R4 had a hydraulic sensor switch. Whenever 4th engaged, power was sent to the lockup. I think it was a B&M part.
Bee Jay

Theiskell

Great, thanks for the info guys! So basically you are just breaking the 12V that goes to the tranny. When the switch in the open position no 12V passes through and no lock up on the converter. Correct???

jetmech

When I installed my 200 I used a 4th gear pressure switch in the transmission. So 12 volts goes through a brake switch then to the 4th gear pressure switch and when the tranny shifts into 4th the pressure switch makes and sends 12 volts to the lockup solenoid. If I am slowing down and step on the brakes if the tranny is still in 4th the circuit is broken by the brake switch and the lockup relaxes. With this wiring method the only time the converter is locked up is in 4th gear and no brake applied. If you have your TV cable adjusted correctly this circuit works very well and is simple to wire. If you step on the gas and the tranny down shifts to 3rd or lower the converter automatically unlocks because you have down shifted out of 4th so the pressure switch relaxes and the circut is broken to the lockup solenoid. Clear as mud right?

TimAT

The only problem with having a switch to disable the TCC is if you forget to turn it back on when you hit the highway, the trans may overheat. The TCC hydraulic circuit forces the pressure to the cooler to nearly double.

I suggested the vacuum switch just for a better feel- if you are in 4th, the TCC locked, and you give it a little more gas (like up a hill) the TCC will drop and you'll get the torque multiplication from the convertor to help you over the hill. It's not needed by any means, but it will give you a little help on a hard pull. Without having to get in the gas hard enough to make a 4-3 shift.

Bee Jay

Two things you gotta have, a trans temp gauge, and a good tranny fluid cooler. I use my old AC condensor as a cooler.
Bee Jay

Michel B

This makes good sense,, and is the way I'm going to go,, but I will add a switch somewhere with very easy access,, maybe overkill but its so simple to add its worth it.

jetmech

If you are running 3:08 gears I think the vaccuum switch is probably a good idea. I am running 3:55 so I rarely if anytime run into a situation where the car is lugging or needs to downshift in normal cruising.

Michel B

I will keep this in mind if required,, right now I am with 3.08 gears but have a 3.36 waiting to be install sometime in the following weeks. I haven't reserched any vacuum switch,, I assume they are redilly available from the big tranny vendors,, I'll check it out.

7PACE8

In addition to the brake switch I used a Lock It Later switch from TCI that lets me set a time delay when my 4L60 goes into 4th and calls for converter lock up. I am currently using 3.70 gears and I have not needed any other control switches. By adjusting the delay (3 seconds) I am getting an even shift sequence and no jerk into 4th gear. Money well spent, it even comes with a wiring diagram

TimAT

GM should also have the vacuum switch '82 pickup 350/700R4(MD8)

Quote:
The vacuum switch sounds like a good idea,, if I understand this correctly, once the lock up is ingaged in forth gear it stays locked unless the brake switch is applied,,ok,,, what happens when the gears drop and no braking is applied ?? Is this where the vacuum switch comes in ?? Also,, does it come into play when kick down is applied ?
04-22-2009 10:38 AM

Anytime the trans drops out of 4th, the 4th switch opens and unlocks the TCC. Same for a detent 4-3 shift. The vacuum switch just holds off the TCC a bit so you don't get a 3-4 shift and a TCC lockup at the same time.