I just finished my V6 to 350 Buick swap on my 83 Regal Wagon. It all went textbook, and is really fun. My question is the TH350 has a lock-up converter which used to be controled by the computer, which has now no purpose whatsoever under the hood. My question: Is there anyway to get the existing computer to lock up the converter still? I know there are aftermarket lock-up kits, but I am a very cheap person, so I wanted to work with what I have. Thanks, Jon
You can rig up a system using a hot wire with ignition on from fuse panel. install inline fuse, (could use any circuit no longer used, or tap into one of the IGN taps on fuse panel) run to cruise control/ brake switch above brake pedal(one set of wires goes to brake lights, other set goes to cruise) , run to toggle switch to be able to turn off ; run from toggle switch to 4 pin plug on side of trans pin. other pin is for ground and third pin is for pressure switch to close to tell computer to apply power to lockup solenoid. some th 350s only use 2 wires, most use 3. you could run the third wire back up as a ground to a relay in line with toggle/ brake switch for full automatic operation. try to draw it below. fuse block (ignition on= power on) ; ; ; brake cruise switch ; ; ; relay pin { ---------------fuse block (ignition on= power on) { ---------------trans pin from pressure switch inside(grounds relay when trans switch closes, completes relay circuit) relaypin ; ; trans pin to tcc solenoid (inside trans) trans pin from tcc solenoid ; ; ground
Had the cruise button activate the lock-up on mine. When you hit the brakes it would un-lock. Steve laid it out for you.
Thanks guys, I went to great lengths to keep my cruise working so I will have to find another alternative. I was hoping I could "trick" the computer into thinking everything was ok and woudl lock it up. Not sure what all signals the computer took in to know when to lock the tranny. Thanks, Jon
Could he not use a vaccum swith to turn on/off (engage/disengage) the convertor instead of a toggle switch also?
Yes, one of my ideas that I am going to try and locate was the use of a vacuume switch used in 80's GM Trucks. It was how they controlled the lock-up converter. Its a vacuum pod, along with a brake switch etc. I know they used it, I just have to find it now. Thanks, Jon
Duh!!! Um, I didn't even think about possibly the easiest way. Are you still using the original wiring harness and dash from the 231? Or are you using the 350 donor car harness? If you have the original harness and the computer is still getting power, you can install a lower temp sensor in the intake and splice in the donor connector (like used on 86& newer gm cars) to make the car computer be happy and operate the lockup system like it did in the original 231 engine.That is, if your intake has space for two sensorsin the front water passage. If you are not using the emission sensor on the drivers sde (yeah, right; emissions:Brow: ), you can install a reducer bushing to fit the sensor.or if using aftermarket intake it probably has at least one plug installed in the water area that can be used. If you live in or near a major city, public libraries sometimes have Hollander or Mitchell manuals that cover every electrical diagram for each specific drivetrain for each specific car; similar books cover emmissions stuff. I'm not talking about the manuals that cover every car and engine generalities like the Chilton and regular Mitchell and Motor manuals; these are BIG puppies several volumes in a row with plastic binders (green and yellow come to mind). Try reference section, 632 or 628 section. You'll know time you see them. It may take some time to get the info, but it is there. PS: the electrical section covering 87 turbo regals was over fifty pages, but it gives all wire color codes to/from computer, and voltages/ resistance in different operating modes (off, on-not running, on -running normal). on different pages. VALUABLE INFO TO BE FOUND!!!
Hi guys, an update on the project. I scored a complete vacuum set up including brake switch on ebay from an 80's GM truck. It has a vacuum switch that completes the circuit to send 12 V to the connector on the side of the trans. My question now is this: The plug from the computer controlled lock up used 2 pins on the harness. The one I got only has one pin, and I am assuming the other pin is ground. Hate to guess with this stuff, so I was wondering if anyone could direct me to the correct power connection to the 4 prong plug in the tranny? Thanks for the help guys! Jon
350-C I read somewhere that you need a vacuum switch and speed senser switch to control the lock up. There wasn't much else needed as some of the controls are inside. Diver
