A friend is going to put a TH400 in his car and says if he uses a stock TH350 torque converter it will increase the stall to about 2200 rpm. Is this true? Does this mean that a higher stall converter is based on weight and/or smaller diameter?
Nope!! A converters stall is measured mainly by size. The smaller the converter the higher the stall. Aftermarket converters are constructed so certain sizes can be various stalls. A 12in converter could be 1500, 1800 or 2000. An 11 in could be 2500 to 3500. A 10in could be 3500 to 5000. But the weight of the car will also affect the stall. A 11 in in a light car may only be 2200 but the same converter in a 3500 lb car would be 3500. Is this clear as mud?
many factors aside from size affect stall speed, like the angle of the vanes on the stator and rotors for one. Stall speed is also affected by the torque output of the engine - Higher torque=higher stall.
Might get 2200 out of some stock TH350 converters, with a torquey enough engine. And the guys who rework them can make them do strange and wonderous things
What they said. I run a 2200 Hughes in the studebaker with 455 pontiac/th400. Love it. What's even better is the one from Lenny @ Ultimate Converter in my 64 cutlass backhalf car. It cost more than my first 3 cars, tho... Getting the right converter for an application is like getting the right camshaft. Talk to the right folks, spend the right money, it works right.