Thanks for the site. Since I recently installed transmission I need to know if the overdrive is working,let me explain. I removed the th200 which had a 2 prong connector. The 2004r has a 4 prong connector I really don't know where to connect the 2 prong into the 2004r. In the 2004r there is only 3 connections even thou it's a 4 slot plug. Heck I didn't even know the th200 had a electrical connection. I dont think my 80 Malibu has a computer.... Very confusing..
Looking for a 2.73 ratio rear end for Malibu
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I'm not knowledgeable on that so hopefully someone else will chime in. You should still have four forward gears but your torque converter isn't locking with that connector unhooked. Need to get that lockup working.
Torsens don't really "disengage". They are probably the quietest/smoothest of the limited slip differentials.
Generally they are on sports cars like Miatas, Boss 302's and make cornering smoother. The car will feel like the outside wheel is going faster through the corner, reducing understeer under throttle. This allows you to apply throttle before the apex of a turn to help the car turn. This isn't natural and gives car with a torsen a slight advantage on an autocross. Newer active vectoring differentials take this concept even further.
A Detroit locker is the opposite end of spectrum. Brutal engagement/disengagement and in a corner under power it makes the car want to go straight, increasing understeer until it overpowers one of the rear tires and the car oversteers... so you can't apply throttle until after the apex... traditional racer thinking and predictable racer handling.
The downside to torsens is they aren't designed to handle massive amounts of torque in a straight line, so slicks and big HP will blow them apart. 7.5's generally blow apart under these conditions anyway, so it should be fine.
Generally they are on sports cars like Miatas, Boss 302's and make cornering smoother. The car will feel like the outside wheel is going faster through the corner, reducing understeer under throttle. This allows you to apply throttle before the apex of a turn to help the car turn. This isn't natural and gives car with a torsen a slight advantage on an autocross. Newer active vectoring differentials take this concept even further.
A Detroit locker is the opposite end of spectrum. Brutal engagement/disengagement and in a corner under power it makes the car want to go straight, increasing understeer until it overpowers one of the rear tires and the car oversteers... so you can't apply throttle until after the apex... traditional racer thinking and predictable racer handling.
The downside to torsens is they aren't designed to handle massive amounts of torque in a straight line, so slicks and big HP will blow them apart. 7.5's generally blow apart under these conditions anyway, so it should be fine.
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Look at where the wires for the plug goes. It should go to a vacuum/electrical solenoid switch up on the engine. Then the brake light switch should have two plugs on it. The non computer cars ('80 models) & trucks (up to '85/'86) with lock up trannys would have the vacuum set up. I can't remember how many wires the plug for the TH200-4R for non computer use. But it might just be the 2 you have, just need a 4 wire weather pak plug, 2 filled plugs for the unused ports. The only thing is figuring which 2 ports to use. I might have a diagram to show which ports.
On my el camino I converted to 2004r it had a 4 pong plug but I only used two wires that ran to a vacuum switch to control lockup on my non computer carb sbc.
You will need 28-spline axles with your Torsen. Your 7.5 has 26 spline axles. Grand National 8.5 axles used 28-splines, but all other dimensions on the axle shafts were the same as 7.5s so buy a used set from someone who upgraded, or some replacements from Summit Racing.
I plan to watch this thread, as I have a 1980 Malibu axle and a 3.73 Torsen from a 2000 Camaro. I have not yet had the time the swap the differentials.
I plan to watch this thread, as I have a 1980 Malibu axle and a 3.73 Torsen from a 2000 Camaro. I have not yet had the time the swap the differentials.
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