The Tork Master is B&M's lowest cost performance torque converter. The Tork Master is an excellent all-around performance street converter. The best 'value priced' street converters available, Tork Master converters come with a new precision pump drive tube and all are pressure tested and fully balanced. The Tork Master torque converter is not recommended for big block or supercharged applications. Stall speed listings are based on engine producing 230 lb. ft. of torque @2,500 rpm. If your engine produces more torque at 2,500 rpm stall speed may be higher. If your engine produces less torque you'll get less stall speed.