rwelchiv

Hi All,

New to the site! Looking forward to the collaboration! Need some help!

Sorry if this has been discussed - don't really see what I am looking for, but may have missed it. If so, would appreciate someone sending me the link!

1981 - I removed the ECM - Holley 4160 - Vacuum Dist. - but not sure what to do about the Torque Converter Lockup.

Can someone please explain to me what a torque converter lockup is, how it works, and why I need it. Still not sure what to do here since removing the ECM.

Thanks much!

CMD1

Welcome to the site! Wealth of information here and always helpful.
I have done a couple of conversions as you have done, this kit is perfect and keeps the transmission alive and 4th gear functioning as intended. Very adjustable, and easy to install.
This will make the car shift properly as long as you have the kick down cable geometry set up properly on the carburetor. Many speed shops sell this kit.
Good luck and be sure to get the kick down cable properly set or you can burn up a transmission fairly quickly.
Other members will have other options and chime in, but this kit has been great for me and my customer's cars.
Welcome to the site!

rwelchiv

All,

Just FYI, the transmission is the 3-speed Turbo Hydra-Matic automatic transmission.

Thanks!

7T1vette

Yes it is....with Lockup.

Lockup feature is built into the converter. It is a hydraulic clutch which, when applied, connects the input side of the torque converter to the output side, so that the converter becomes a direct-drive device with no hydraulic losses. But, that clutch is not sturdy enough for much torque...maybe 200 ft-lbs...max. Overdo it and the clutch fails....or the converter fails.

Lockup is supposed to drop out (go back to hydraulic converter mode) when going up a hill or applying more than so much accelerator movement when in high gear. The ECM managed that so the lockup system would survive. Oh.. BTW....running that transmission without applying lockup is also not a good idea. When not using lockup, the converter generates more heat that expected and, if left that way for long highway runs, can fail the transmission. So, lockup NEEDS to be applied when called for; and it NEEDS to be dropped when significant acceleration is required. That means [for most folks] a lockup controller should be installed to correctly manage the lockup clutch.

That's what it is: that's what it does; that's how it works; and that's what it needs. What you decide to do will determine if your transmission will live--or die prematurely.

scrappy76

There is also a kit that is external that uses a pressure switch an a toggle switch so you can turn it on or off yourself. That is what I use. Lockup is definitely best to use especially if you do alot of highway driving. It helps keep the heat down in your transmission. Alot of back and forth discussions out there about how you will kill your transmission of you do not have your lockup hooked up.


The main thing is to make sure your TV cable is adjusted correctly or you will kill your transmission in a heartbeat.

rwelchiv

7T1vette and scrappy76,

Thank you, thank you, thank you. This is the most extensive explanation I've seen yet on what the lockup does and how it works.

I will ensure my TV cable is connected correctly and install an external kit.

Thanks again so much for taking the time, sincerely appreciated!

scrappy76

look on you tube, for monsters transmissions they also have video on the external lockup with toggle switch.

7T1vette

The problem with an external switch is that no one remembers to flip it off in an 'emergency' situation (panic stop,. something in the road, etc). A controller will do that for you.

Not having it drop out can be a dangerous thing in some unusual circumstances. Let "Bubba" be Bubba and throw a toggle switch in there. Not for me....

rwelchiv

7T1vette - understood and agreed; doubtful I would remember to flip the switch when needed.

Hope you don't mind one last question, I could probably Google this but.....I was hoping not to have to bust into the tranny. Are you aware of an external controller that I can throw in my Vette to "mimic" the ECM in this case.

Hope I'm asking the right question...

Thanks again for your time!

7T1vette

Transmissions with lockup clutch have electrical connectors that are accesses on the exterior of the main case. All aftermarket lockup control modules are external to the transmission and use that connector to link with the transmission.

rwelchiv

Got it. Was hoping that was the case. Thanks again 7T1vette!

rwelchiv

Hi 7T1vette and scrappy76,

Hope you're both still there and doing well and don't mind answering a few more questions about this torque converter lockup.

1. Possible you could help me identify my tranny. I am assuming it is the TH350C as that has the lockup and the TH350 does not. Want to make sure I am getting the right lockup kit. Pretty sure I don't have the 2004R or the 700-R4. Is this correct? Need more info?
2. In my shop manual, I am assuming that the TCC solenoid is the torque converter lockup solenoid. Is this correct?
3. I believe this solenoid is actually in the tranny, is this correct?

Sorry for bringing this back up. Had to step away from the car for a while and when I got back into it I ended up needing to do a top end on the engine.

Ready now to address this lockup.

Thanks in advance!

Golferdad

I’m trying to find a 200 4R transmission now,for my 1981,I just replaced the heads,intake,carburetor,headers,and HEI distributor.

Golferdad

I bought a 1981 4 months ago,and it has a th350 transmission which is a 3 speed,and I hate the way it’s geared and shifts into third gear,the other 2 transmission are 4 gears if I’m not mistaken,that’s why I want to switch mine to the 200 4R transmission,and I haven’t removed my wires yet,but did remove the box inside the battery box,which it ran perfect before I tore the engine apart.

rwelchiv

Hey Golferdad,

Yes, agreed, the 4-speed tranny seems very appealing. Might also go with the manual transmission.

In the meantime, need to get this torque converter working right on the 3-speed I have. I ripped out the ECM when I put the crate motor in, but left the tranny alone. All the vacuum and linkage to the transmission is good I believe, just need to finish this TCC.

Good luck with your transmission switch.

riverracer au

there's many ways to the lock-up, manual with a switch on dash or automatically via speed related

i used the B&M kit when i did the 700r4 into my '72 many years ago.

also added a brake pedal dropout switch and a vacuum switch dropout for when under hard load.

rwelchiv

Hi riverracer,

Wow, from Adelaide, that's awesome. Was down there back in 2000 when I worked in rapid prototyping.

Yeah, that's exactly what I am looking for: a kit for a TH350C where I don't have to go into the tranny, has the vacuum and break dropout, engages either via speed or vacuum, and a switch just for when I feel like it.

Haven't found that yet, but will keep looking.

Thanks for responding.