Stall Convertor

[axisg]

OK call me newb but can someone please explain how a stall convertor works in everyday driving situations? I think it would be a real PIA.

Reason is I am looking at a car with a speedshop-built th350 trans with a 2300 stall and 3.73 gears ( posi ). I really want a 4speed cruiser but this car has all I want otherwise ( 350, AC, PW, PL, Buckets & Console, 3.73 Posi... )

Otherwise does anybody wanna swap a built th350 & crossmember for a good 700r + crossmember straight up ?

 

[87MonteSS]

The stall speed is the engine RPM at which the converter reaches full fluid coupling, IE: it is no longer slipping. The goal is to allow the engine to reach a higher RPM, producing more torque/horsepower before fully engaging the transmission.

The car will still move and drive below the stall speed, but the converter is slipping during that time. As a result heat is generated by the converter.

Ideally you want to be driving with the converter at fluid coupling speed, so in your case 2300 RPM or more. Driving in the city would almost always be below the stall speed so there would be heat buildup and loss of fuel economy.

3:73 gears and a three speed would put you around 1900 RPM @ 30 MPH in third gear, assuming you're running somewhere around a 245/60 or a 215/65 tire out back. This is well below the stall speed and could cause early failure of the transmission.

Going to a four speed automatic wouldn't change this if you kept the same converter. It would help on the highway, but 2300 RPM stall with a four speed would get you in around 65-70 MPH before fluid coupling.