Lock-up system for TH200 4R ?

Discussion in 'The "Juice Box"' started by Atbb, Feb 1, 2016.

  1. TheSilverBuick

    TheSilverBuick In the Middle of No Where

    This really seems a much ado about nothing IMO. For what it's worth, the TCC takes about 1 second to lock and unlock, so if you lock the rear wheels up, even with a brake switch, there is no guarantee it won't stall in a panic stop. Besides if your engine stalls you still have two good presses of the brake pedal with power, and if you still aren't stopped after that much "panic" braking you should be going slow enough that a non-powered assist stop shouldn't be that big of a deal. Power steering likewise, if you are moving at any real speed the power assist isn't doing a lot of assist, it only gets hard to turn the wheel at sub 5-10mph, and if your wheels are locked up (fronts should lock before rears and no ABS!) then you don't have steering anyways. Heck, many old engines simply stall from fuel slosh in the float bowl under high "panic" braking, no transmission help needed.
     
  2. elagache

    elagache Platinum Level Contributor

    Cruise control as starting point? (Re: Lock-up system for TH200 4R ?)

    Dear Chad, Greg, Ken, Jens, Patrick, Sean, Randal, and V-8 "classic cruiser" types,

    I didn't know about a very interesting product when I last looked into a controller for the lock-up torque converter. That product is the Dakota Digital cruise control kit for cable driven speedometers:

    http://www.dakotadigital.com/index....uct_id=46/category_id=477/mode=prod/prd46.htm

    By definition, a cruise control needs inputs for the car's speed and needs to disengage whenever the brake or accelerator pedal is pressed. Without doing anything else, I would expect that you could find a signal that indicates the cruise control is engaged. If you send that signal through sufficient relays, you should be able to turn the lock-up converter whenever you turn on the cruise control.

    That's not exactly what you want, but it is already a nice way to implement it. You'll get the most benefit from the lock-up converter while cruising. If you go this route, you can install something that looks like it belongs in your car and most of the electronics is taken care of by Dakota Digital.

    But if you are greedy [​IMG], you could try to hack this system.

    If you aren't greedy, you might try to nudge Dakota Digital to design an add-on to this product that would control the lock-up converter in reasonable situations beyond using the cruise control. If you have the brake, accelerator, and speed, you have most of the data you need. It might be desirable to add the vacuum switch to provide an additional parameter. With all that input, I would expect the logic would be trivial and an engineer at Dakota could come up with a prototype in an afternoon.

    I think this is a very appealing away to make the controlling the lock-up converter practical and stylish. Some guys don't mind cluttering up their dash with buttons that don't look original. However, there are those who have the opposite point of view!

    [​IMG]
    Cheers, Edouard :beer
     
  3. black70buick

    black70buick Well-Known Member

    Sean this is plausible when there is a transient effect in place, say from a bad (or floating) ground and/or a high resistance, that would cause a failure for the solenoid to electrically discharge quickly as intended. In your case, I would believe this had happened and everything went down hill from there. In some applications an H-bridge is used to basically push or pull the electrical charge of a component - think of it as a faster "drain." Sorry. Now back to your regularly scheduled thread.
     
  4. sean Buick 76

    sean Buick 76 Buick Nut

    I tried this on 3 of my vehicles that had lockup converters and they all stalled when I slammed on the brakes so I added a brake switch to all 3 and they never stalled again after that.
     
  5. black70buick

    black70buick Well-Known Member

    Yikes, could be bad design in the circuit, if the truly did put it in the design, causing the transient . :Do No:
     
  6. sean Buick 76

    sean Buick 76 Buick Nut

    Not much to the circuit I was using a toggle switch not the gm designed setup. No internal mods to the trans just wiring the toggle in the ground loop and giving the trans 12v from the battery. As factory had it where it always had power and the switches on the ground. I know 100% there were no faults in the ground or power wires to the trans as i ran new wires for each.

    Once I added the brake switch all 3 vehicles have never stalled since.

    I guess that's why gm added the brake switches.

    Ironically the brake switches often failed over time resulting in no lockup and overheating trans. A trans guy told me that is a main reason the early 700r4 were burning up from overheating... No lockup as the brake switches we're going bad over time.
     
  7. Atbb

    Atbb Well-Known Member

    Hi,

    thanks for your input and your discussion about that subjet, I`ll go through the things you`ve mentioned as soon as I got the trans out of the car.

    Jens
     
  8. chrisg

    chrisg Silver Level contributor

    Replying to this thread a little late but thought I'd toss my 2 cents in, as I think I have a setup that no one else has mentioned. I use both the TCI and the B&M kits in series. I have the TCI switch connected to ported vacuum on my carb, so that it unlocks when I let off the gas - makes coasting smoother and has the same effect that a brake switch has. I originally ran with just this setup, but with my 3.23 gearing I found the converter was locking up too soon and causing the engine to lug, so I added the B&M kit as well and have been very happy with this arrangement. Finally, I also have a toggle switch that allows me to lock it up in 2 & 3 in addition to 4, mainly for use at the drag strip. I have a multi-disc clutch in my converter that can handle full-throttle lockup, so I can get away with doing that without destroying the clutch.
     
  9. Fox's Den

    Fox's Den 355Xrs

    I noticed that you said you can lock up the convertor in 2nd 3rd and 4th for drags trip use. I can do that with mine but have never tried to lock up in 2nd gear and leave it there going thru 3rd and wondered if you have ever done that. I have a Pro Torque convertor and paid good money for it but I was only locking up in 3rd gear at the track.

    Guy
     
  10. TheSilverBuick

    TheSilverBuick In the Middle of No Where

    It probably depends on your rear gear and how wide or narrow your engine power band is, but usually you want the torque converter doing it's job on every shift and then just let it lock up in 3rd. If your power band is wide or your gears steep, it may show benefit to lock up sooner.
     
  11. philbquick

    philbquick Founders Club Member

  12. TheSilverBuick

    TheSilverBuick In the Middle of No Where

    The auction site is goofy looking through the firewall I'm seeing it through, but I do not see any mention of an "internal lockup" without electricity. The lockup function is controlled by an electric solenoid, and the only way I can think of by-passing it would be to install some kind of plug that is the equivalent to the lock up setting of the solenoid as the valvebody does not allow the converter to be locked in 1st gear. So basically a "no electricity internal lockup" would mean it immediately locks up when shifting into 2nd gear. Electrically, there is also a pressure switch that closes it's contacts in 4th gear and that's how the lock up in only 4th is usually wired. Or there is transmission voodoo I'm unfamiliar with is involved.


    Here is a picture of when I lost a bolt from the solenoid on mine. The leakage from this caused line pressure to drop, so the solenoid cannot be left out.
    [​IMG]
     
  13. sean Buick 76

    sean Buick 76 Buick Nut

    CK performance trans are normally setup with internal auto lockup with no wiring so it is common, just not common knowledge and I do not know how they do it.
     
  14. TexasT

    TexasT Texas, where are you from

    Iirc the early diesel 2004r had a hydraulic lockup in a different vb. This only lasted a short time. I'd have to look at some od my materials to substantiate.
     
  15. elagache

    elagache Platinum Level Contributor

    CK "always on" - not internal (Re: Lock-up system for TH200 4R ?)

    Dear Randal, Sean, Rich, and V-8 Buick fans of overdrive transmissions,

    I can't be sure my CK 200-4R was different in some way, but it came with a 1 wire lockup torque converter and the advice of simply connecting it to +12V. As CK described it, when you went into overdrive, it would immediately lockup and when you downshifted it would unlock automatically.

    I can't be 100% sure about this, but this seems much more plausible an explanation for an automatic lockup converter than anything else thus far proposed. Of course if you make a panic stop, will the transmission downshift in time, or will your monster torque Buick engine destroy your 200-4R before it can shift?

    I decided I didn't want to find out "da' hard way!" . . . . [​IMG]

    Cheers, Edouard
     

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