ManFromEagle

I have installed a 200-4R that I got from Bowtie. I bought their external wiring kit for the lock-up torque converter. I only needed their external wiring kit as all their trannys come with the internal wiring and solenoids already installed.

I understand the concept. I modified the kit and added a toggle switch in the line from the brake switch to the tranny so I could defeat the 4th gear lockup if I choose.

I would like to know if this system will work OK? I have some engine problems at the moment so I can't just go test drive it.

There are a few wiring kits that also have vacuum switches. My understanding is that they unlock the converter at large throttle openings when the vacuum falls.

What do you think? Is the system better with a vacuum switch? I could custom wire in a vacuum switch but I can't find one.

I have made a few assumptions. It must be a normally open switch that closes when vacuum rises above a set value. I assume that value would be around 5" of vacuum. I do not know how much current the transmission solenoid draws but the bowtie kit has a 10 amp fuse so It has to be less then that. Are my assumptions correct? If so does anyone know where you can purchase a switch that meets these requirements?

Buffalo Dude

I would think the TV cable would be sufficient. If you floor it enough that you would want to unlock the TC, you would probably want it to downshift, too, which the tv cable will do by itself.

EDIT: just reread what you wrote, and now I'm confused. Why would you want it to lockup when the vacuum is higher (and in fourth), rather than whenever it hits fourth?

redwingvette

The way mine works is; the convertor locks as soon as it shifts into 4th. I added a toggle switch so I control when it will lock. The vacuum switch only allows it to lock if you are above a set RPM which is basiclly the same thing. The problem with depending on the TV cable to control it is that the trans will not downshift if you are just slowing down so the converter won't disengage so the engine may start to chug when you are going about 30mph.

markdtn

I have the vacuum switch now. With 3.7 gears and 700R4 it locks and bogs down at about 35 mph coming off a stop light slowly. If you really get into it, it is better, but you can't leave every stoplight at 1/2 throttle or more. What you have will work OK. Just turn it on at cruising speed and remember to turn it off. The best way is to allow a computer to do it, that is next for me. I have TPI and a Howell harness. They don't make a harness for an automatic, but they tell me that the ECM still has a lockup speed built in (about 45 mph) they think.

bobs77vet

can only speak to the 700r4 lock up torque converter but i put that toggle switch "in line" as you did and it works fine. my problem is different then Markdtn, my problem is not from a start but when decelerating and then accereraling in the 35-40 mph range under light throttle conditions...like cruising around on back country roads and then the car will be in lock up at 35 mph at like 700 rpm....not much fun...the vacuum switch wouldn't solve my problem, i need an RPM activated switch but the MSD RPM switch created too much chatter inthe relay.

ruby76

I put a TH350C in my old truck a while back. I wired the lockup torque converter to a toggle just under the dash. I manually switched it on when I wanted it locked and unswitched when I didn't. It was cool to seee a 200-400 rpm change on the interstate. I didn't mess with any other wiring kits etc. I got the wiring plug from a junkyard, then ran wire to the dash and that was it.

norvalwilhelm

I used a relay. I energized the relay by a push button switch which locked the torque converter. If you repushed the button on the switch it disengaged the converter. The brake light was also hooked to the relay so anytime the brakes were touched the relay received a voltage from the brake and turned the converter off.
This allowed you to energize the system any time for driving but anytime the brake was touched the relay diengaged turning off the lockup.
The only problem I found is that if the rpm wasn't high enough and I pushed hard enough I broke the lockup feature loose and would burn the clutches. Not enough lockup for me.

UKPaul

Assuming that the brake switch is an additional one that has it's contacts opened when the pedal is pressed, then it'll be fine. What I've done is taken power from the TCC brake switch & just gone direct to the trans with it (haven't found the time to fit a manual switch in the circuit). Whenever the trans shifts into OD the converter locks. I only shift into "D" when above 55-60mph, so lugging isn't a worry. If I don't shift down into "3" when slowing down the trans will stay in OD (locked) right down to 1000rpm (40mph)! Shifting between "3" & "D" isn't a problem for me as I've always driven stick shifts &, for the street driving I do, moving the shifter is probably easier than groping for a toggle switch to throw when speed increases or decreases. When running in OD with the converter locked I don't have any problems with breaking the converter loose as I don't think my anaemic L81 engine has the power to do it If I accelerate at anything more than gently when in OD then the trans automatically shifts down so I don't have any issues at all with it. Apart from one: I've got v. loud pipes, so when it shifts down any TVR, M3, XK8, SL500, Boxster, etc, etc around me thinks that I want a race :rolleyes (don't even consider taking on an SL500 with a fairly stock 350 C3, it'll only get embarrassing!).

Something to be aware of is warming up the trans. Mine originally had a Th350C under computer control & the converter wouldn't lock until the coolant reached operating temp. I think this was to allow the trans fluid to warm up, as if I drive the 200-4r from cold & stick it in OD the temp guage doesn't move. I have to do a few miles in the lower gears so that the slipping converter heats up the fluid. If you've got a toggle switch in the system then I'd suggest switching it so that the converter doesn't lock for the first few miles after a cold start. I spoke to BTO about running the fluid cool & they said that it was far better than running it too hot, but wasn't ideal. Have you fitted a temp gauge? If not then it may be worthwhile, even if only temporarily. I found that mine was getting far to hot & had to fit a trans cooler. Another forum member is doing exactly the same (today if it arrived). If you do fit a cooler then don't go overboard on the size. Mine cools it to much! "Fit the biggest trans cooler that you can"???? Nuts! Not in normal street use you don't, the fluid will never get up to temp - and this isn't a foggy little cold outcrop in the north Atlantic, the 1st summer I had the 200-4r we had temps of 100F & it was still difficult to get the fluid up to anywhere near 160F with the cooler fitted.

p.s. enjoy the trans, it transforms highway driving. 3 years on and I'm still getting on motorways (Highways? Interstates?) in "3", accelerating up to just a tad over the limit, listening to the engine revving away & the exhausts roaring away, just as it was like with the th350, & then I knock it into "D" & the world becomes peaceful again The fuel gauge stops moving down, the engine turns over at a lazy rate & the exhausts just burble. Yeah, I know it's childish, but what's the point of buying toys & not playing with them? It used to turn 3000rpm @ 70mph, now it turns 2000rpm@75mph, the legal limit on motorways is 70mph and a "tad" is open to negotiation
The lower ratio bottom 2 gears are also better. A couple of weeks back I think that I may have even heard a chirp from the rear tyres on a dry road when doing some WOT "testing" (testing it against an M5 - again, don't bother!). It was probably nothing, maybe just a normal C3 squeek but, whatever, it leaves the line quicker than it used to.

ManFromEagle

The TV cable may be sufficient. I don't know yet. I was checking everything I could find on the internet and over half of the wiring kits had vacuum switched. The idea is that you would not toast the lockup plates in the converter when really into the throttle. When the vacuum drops the switch goes open cutting power to the lockup solenoid in the tranny. The vacuum is higher when cruising and that's when you want the converter locked.

Anyone have a source for these vacuum switchs? Was my assumption correct on the amount of vacuum at the switch point?

ManFromEagle

There was a long thread that you started about the MSD RPM switch. I followed it hoping you were onto something. I have a stock HEI distributer but was thinking that an electronics tech at work might come up with a circuit that could tap into the tach wire and do the same thing you were trying to do. Have whatever gizmo they could come up with run a relay. The way I figure it the thing would have to have some build in hysteresis in the switch point to avoid the buzzing you experienced. Still mulling it over in my head.

THe vacuum switch idea would be for the other extream where you floor and the kickdown does not work for some reason.

ManFromEagle

Your comment about just shifting down to third when coasting on an entrance ramp, etc. is probably a good work around.

I am also looking forward to the lower RPM's on the highway. From my point of view it will make the car more civilized to drive.

One more point. The last time I was in England I didn't think they cared about the speed on the motorways. In every 70 MPH zone I was in people were constantly passing. Someone told me just keep it under 90 and you won't have a problem with the cops.

I will say the English know how to drive. People in general stay in the appropriate lane based on there speed. They only pass on the right (This is England folks). Here in the states you have people poke along in the left lane and passing on both sides of you.

I also love roundabouts. That's the way the whole world should be. That makes so much sense to keep the trafic moving. We had them in New England where I originally came from.

bobs77vet

have not given up on this idea....another forum member who is a electrical guy is thinking about this idea....its way over my head... we will keep you posted.

markdtn

My latest JEGS catalog has a B&M kit that has a speed sensor. Apparantly you can pick a speed to lock the convertor. It was about $150. That might be good for you.

Fevre

In my Formula I have mine hard wired to a toggle switch so it is full manual, I can lock it in 2, 3 or OD. Since it is a pleasure car I do not mind working the toggle but if it was a DD it would be a pain. I am going to switch to a ratchet shifter (someday) and figured I would get a handle that has a switch to use for the lock.

bobs77vet

i looked at those the idea is right on the money, but i don't think we have the room for it, since the adapter connects right to the tail shaft speedo cable and preliminarily looking at the two, looks like we will run out of space before its alls hooked up. i guess maybe you could hook it up at the cruise transducer? i tossed mine so thats out of the question.

markdtn

I have a screw-on VSS on my 700R4 at the transmission. Yes it is very tight. I got one of those 90 degree adapters and it works much better.

bobs77vet

next time you have it up in the air i would like to see pictures of that....i would like to use something like that if it will work the first time...the MSD RPM fiasco was such as waste of good time i am hesitant to chase any more ideas unless they have good degree of sucess. what are you using the VSS to control or monitor?

markdtn

It will be at least a week before I will have an opportunity to take photos-sorry. I am using the VSS because I have Tuned-Port fuel injection and it needs a VSS input to the computer.

BSeery

I remember someone was going to try and use a RPM switch, but I knew that wouldn't work. The reason is that when you hit the set RPM - say 2000 RPM - and let the converter lock up, your RPM's would drop below 2000 RPM and then the switch would open again and unlock it again. That is until it reved up again from being unlocked and went past 2000 RPM once more --- see the destruction that will happen ??

There a 3 ways to do this. - Stock wiring and just keep it in 3rd gear until you are on the interstate. This is how I currently keep my engine from bogging down. Mine will shift to 4th at 45 MPH and immediately lock up as well. When I accelerate it will cause detonation because of the high load, low RPM and crappy azz 91 octane fuel we get out here.

Method 2 - in line switch. Drive around in 4th and let it shift to 4th but have a manual switch for lockup. Make sure that it's still routed through the brake switch so an emergency stop will still disengage the lockup. This is the method I am going to next.

Method 3 - MPH controlled switch - Either through a computer or other source (B&M makes a REALLY nice switch - http://static.summitracing.com/globa.../bmm-70244.pdf) you delay lockup until a set MPH, say somewhere around 65 mph ish.

bobs77vet

that someone was me....the MSD RPM switch worked fine in controlling the lockup....didn't have any of the cycling that you mentioned....the problem was that the MSD RPM switch "would leak to ground" and it was making the relay chatter. that was my problem and driving a round with a buzzer going off wasn't my idea of a fix.