Lock Up Torque Converter

[BigTom1957]

Some one talked about shift kits in a previouse thread as well as pressure switch to raise the lock up point of the torque converter. I have found the trans-go shift kits but can not find any info on the pressure switch, If anybody has any info on this? part no. etc. I would appreciate it if you could reply. TIA BigTom

 

[SIXFOOTER]

Which Transmission? I don't think I would worry much about the pressure switch set point. The control circuit for the lockup is controlled thru a couple of points, the pressure switch is just there for part of it

 

[BigTom1957]

Its an 81 with the th350c, Its the stock tranny with 350C.I. motor that i built a little, cam, higher compreesion pistons, and headers. I havnt driven it yet as its not quite back togeather . I thought now would be the time to do any tranny mods as its out of the car and easy to work on, So I am going to do the trans-go setup.

 

[SIXFOOTER]

Thats a good shift kit. How many miles on that tranny? The next real upgrade shoud be a 2004R, it has a better gearset plus overdrive in 4th. But that TH350C is a very good unit as long as the clutches are not toast. Just put the shift kit in and see what you get, I think you will find the lockup works fine

 

[Bills money pit]

Tom: I installed a trans-go shift kit and I am very satisfied with the performance. During the install, I noticed the valve body had a threaded plug opening where previous models had the pressure switch. I went to a local trans shop and they let me look through their stock of valve bodies. I found several switches each one having the mph lock-up number on them. I selected one that was a 32 mph lock-up. I installed it in the threaded hole I previously mentioned and removed the connections to the 2 gear pressure switch and attached them to the pressure switch I installed. The previous lockup speed was about 25 mph and now it is about 35 to 38 mph. At 25 mph, I felt this was lugging the engine. Now at 35 mph, no more lug....Hope this helps! Seems pressure switches are getting hard to find. The trans shop had only a new one that was a 54 mph switch. I felt this was a bit to high, but it would prevent lock-up until highway speed. To me, the ideal lock-up switch would be about 38, but I could not find one. Another good benefit of the added pressure switch is if the ECM lock-up functions fails, the trans will still lock. As I know it, the ECM provides a ground for lock-up, this function is now accomplished by the added pressure switch. Also, as I know it, when a programmed speed is reached, a sensor is tripped by the speedo mph and power is sent to the pressure switch and the ECM provides the ground, now the pressure switch will provide ground. I hope all this is understandable as I am just a plunker....

 

[BigTom1957]

Thats the info I was looking for. Thank You, Big Tom