transmission/Lock up question on my set up

[klaird]

I will soon be putting my rebuilt v6 231 into an 85 olds cutlass daily driver/fun car. The engine has very little performance changes made to it. It has been bored .030 due to ring damage, and a different cam was put in it. I think it's a comp cam k69-235-4. (a "competition valve job" not sure exactly what that is shame on me). I have a 4 barrel edelbrock performer intake for it, but I have been told that a 4 barrel intake/carb will only suck more gas and is not suited the best, so I'm planning on installing the original 2 barrel intake with an early model Rochester 2 barrel carb (pre electronic) to see how that performs. The car currently has the original 3 speed auto transmission and I'm assuming original torque converter. I also plan on taking out the computer and emissions devices. The car currently has the original 2.4 rear. I also have a 3.73 posi rear from an 88 MonteSS as well as a 200-R4 (with stock torque converter?) from a 1986 cutlass. My goals are to first get the engine running and work out any kinks and get it to a dependable daily driver status. But once I have all the kinks worked out I am soon going to be looking at making some upgrades. I would soon like to put on dual exhaust and also soon putting in the 3.73 rear and 4 speed. At what point do I concern myself with torque converter (lock up versus standard) and selecting stall speed? Or is it not something I have to be concerned about at all based on the fact that I have a low horsepower engine? Is there a way to ID existing torque converters to determine which ones are lock up vs non lock up and stall speeds? I would like to ID what I have as well as donors from junkyards.

 

[darbysan]

The 200-4r will have a lock-up converter. You will have to go aftermarket to provide the means to lock it up. Many are available, from a simple toggle switch you manually set/release, to the automatic variety. Your TH350 may have lock up in it now. Check to see if it has a 4-conductor plug on the side with wiring. If so, it is lock-up controlled as well, and will need the same aftermarket devices. Stall speed is the rpm at which your torque converter stops slipping ( like releasing the clutch). Too high a stall speed, and the engine has to rev pretty high to get the car rolling, and will be slipping a lot during driving. Stock is usually somewhere around 1500. In the 200-r4, you could see them in the 1800-1900 range in the MCSS and about 2100 in the GN. Usually they are not marked. The GN does have D5 printed all around the perimeter. For a daily driver, I would think you would be happiest under 2000. This will get your engine up into the RPM range where it makes power quickly, yet won't be slipping a bunch when driving.