What is a stall converter -What does it do


#1 Eagles fan
May 1, 2007
Obviously I am a beginner. I have learned a ton over the last 6 months but explain "stall converter" to me. Hey, you'll never learn if you don't ask.

Thanks guys/gals
The amount of slippage the converter allows before forcing the Trans to spin.

Well at least this the way I under stand it

I bet some else will be able to give you a better explanation.
All converters have a certain stall speed. Aftermarket high stall converters will obviously have a higher stall speed that a stock converter. Some people check stall speed by the foot brake method. This isn't the correct procedure to check the true stall of a converter, but it will give you the idea of what stall speed is. In order to do this, press and hold your brake pedal and gas pedal at the same time. Look at your tach and see what the maximum rpm is that you can attain before the tires begin to spin. For safety's sake, you may also want to set your parking brake. This will be your footbrake stall speed. If your car happens to have a transbrake, then you can test the true stall of the converter.
Technically the stall speed of a converter is the maximum speed an engine can spin the converter if the output was locked in place.

Companies advertise a stall speed and if you do some research you can find out what power level that occurs at. That's good info to have as the same converter that stalls at 2500 rpm behind an engine with 250 hp could stall at 4500 rpm behind a 600 hp engine.

Edit: I realized that doesn't answer your question. A stall converter is basically a device that forms a fluid coupling between the engine and the transmission. It basically takes the place of the clutch in that it transfers the energy from the engine to the transmission. A fluid coupling is needed so that when you put it in gear it doesn't stall.