B&M HoleShot 3800 stall converter for Ford C4 transmissions are an excellent choice for vehicles with engine modifications, particularly big cams that tend to reduce low end power and torque. The higher stall speed of this converter will launch the car in a higher rpm range where more torque is readily available, resulting in quicker acceleration. Holeshot converters feature furnace brazed impeller and turbine, new precision steel alloy pump drive tube, new heavy duty needle bearings between the stator and impeller (not a thrust washer) and needle bearings between the stator and turbine. Other features include a new turbine hub and new springs and rollers in the stator. This converter has a 11.438 inch bolt circle, 26 input spline and a 1.375 inch crank pilot. If your vehicle is equipped with a plate type nitrous system, please refer to the Nitrous Holeshot line of converters. Stall speed listings are based on engines producing 230lb. ft. of torque at 2,500 rpm. More torque at 2,500 rpm will give you more stall speed, less torque at 2,500 rpm will give you less stall speed than the stall speed ratings indicated.