Why is a torque converter the best performance upgrade money can buy?
Theoretically, for maximum acceleration the stall speed of the torque converter should match the peak torque rpm of the engine. A good explanation for the way it works is this: when you go outside jogging you start to breathe in and out faster and harder. Well the same thing goes for a performance engine. The engine is breathing in and out harder and faster, at a higher rpm. If a high performance engine makes power at a higher rpm, then a higher stall speed torque converter is what you need to put more power to the ground quicker.