Converter lockup using ECU without Computer carb/ign?

[85 Cutlass Brougham]

I have been thinking about this for a little while now. I am using a non computer Q-Jet and HEI on my 355, but do not have the converter lockup function hooked up on my TH 200 4R. I know kits exist to make this all work together, but could I use the ECU to run just the lockup function if I have the VSS connected? Does it require other inputs to give the TCC the signal to operate, such as the TPS? I would of course also have the brake pedal switch for disconnect hooked up too. I would like to make this function work for fuel economy reasons, but do not wish to buy a kit since a 5 speed manual is planned for the future.

 

[BILL DEMMER]

basically, the whole system has to be operating properly to get the ecm to do a lockup.


bill

 

[dougfather]

http://www.robertpowersmotorsports.com/CCC.html

He makes mention of how to make a lock up controller.

 

[85 Cutlass Brougham]

Yes he does have a way to do it, but it requires dismantling the transmission. I don't want to go through the trouble of removing the trans and front pump to make it all work if it can be avoided.

Anyhow, I have a booklet from GM called "Fundamentals of Computer Command Control", which is a bit bigger than a TSB, and is part of their "Product Service Training" series. It states that the computer uses MAP sensor, TPS, TCS, and VSS signals to determine when to use it. I can run all of these sensors except for the TPS. Now I am also curious if these is a way to use a TPS from a TPI car, but have it take it's reading off the throttle shaft on the side of the car opposite the throttle cable bell crank. Another option would be a resistor connecting the 5 volt input wire and the output wire such that it tricks the computer to thinking it sees the 20-70% throttle opening it requires for converter lock up. I was just wondering if all this is needed, and if anyone had made this work before.

 

[JESSE]

lock-up

the kits i've seen use a pressure switch on the fourth gear port of the trans,as soon as tou get in fourth it turns on the clutch .when you down shift out of fourth it disengages pretty simple 😀

 

[BILL DEMMER]

http://www.oldspower.com/vb/showthread.php?t=17690


bill

 

[megaladon6]

all you need is to run power through the brake switch (off when you step on the brakes) to the pressure switch. if you wan't lock-up in 2nd and 3rd you need a different pressure switch like what bowtie overdrives carries.

 

[85 Cutlass Brougham]

I want it to function as it would if GM had built it, meaning it won't immediately lock up in 4th gear, sort of a fuzzy logic kind of switch. If I am using WOT, I want it to stay unlocked, then lock up when out of full throttle. Maybe I could just use a momentary switch like you would for a nitrous application for full throttle, and a closed throttle switch so that it is not on when the throttle is fully closed. I think I will try my ugly TPS idea off a junk car. Either that, or the vacuum switch from a pickup truck without computer. I'll probably revisit this in a few weeks after it's painted and I am working on assembly.

 

[malibuSSwagon]

84 and earlier s10's w/ the 700r4 have a vacuum switch setup in them, because they don't have ecm's. The switch is connected to the brake pedal switch as well, and to the 4th gear switch on the transmission.

 

[megaladon6]

i believe that between the TV and the pressure switch it comes right out of lock-up when you hit the throttle.