[screamingchief]

torque converter is a hydraulic fluid coupling device (think clutch) that has the ability to multiply torque up to a specific rpm, depends on many factors the amount of multiplication,slip,stall etc. The inside is made of four basic components the two halves(rotors), a stator, and a sprag,basically think of a fan blowing on another fan one larger one smaller with a shaft on it, big fan makes little one spin harder until sprag locks up (theroretically). For street use you generally would want cruise rpm higher than adv. stall speed to avoid excessive slippage and heat buildup (use a trans cooler w/higher than stock converter)