Racing Torque Converters

Dummy converters, or as some people call them, hollow converters, arequickly becoming a popular item with stock class short-track teams.They allow the racer to use a direct-drive setup in a class thatnormally would be running a working converter or a "stock appearing"converter.

Standard Torque Converter

A torque converter is a fluid-coupling devicethat also acts as a torque multiplier during initial acceleration. The torque converter consists of four primary components:

1. Cover: Thecover (also referred to as a front) is the outside half of the housingtoward the engine side from the weld line. The cover serves to attachthe converter to the flywheel (engine) and contain the fluid.
2. Turbine: The turbine rides within the cover and is attached to thedrivetrain via a spline fit to the input shaft of the transmission. Whenthe turbine moves, the car moves.
3. Stator: The stator can be describedas the "brain" of the torque converter, although it is by no means thesole determiner of converter function and characteristics. The stator,which changes fluid flow between the turbine and pump, is what makes atorque converter a torque converter (multiplier) and not a fluidcoupler.
4. Impeller pump: The impeller pump is the outside half of theconverter on the transmission side of the weld line. Inside the impellerpump is a series of longitudinal fins, which drive the fluid around itsoutside diameter into the turbine.

The Powerglide Transmission

The two-speed Powerglide transmission has become an increasingly rarefind in junkyards and old cars. Aluminum-bodied Powerglides wereproduced between 1962 and 1973 (a cast-iron version was also produced,but nobody wants them for racing). People pay anywhere from $50 to $250at a junkyard nowadays just to obtain a beat-up one. If you're looking,target old Chevy IIs, Chevelles, Camaros, Pontiacs, and some GM trucksfor Powerglide transmissions. The first generation of Powerglides(1962-'65) have pump gears on the rear support. The '66-'73 Powerglidesare considered better because the pump gears are located at the front ofthe transmission, the preferred location.

Race car builders oftenconsider the Powerglide first because of its light static weight, strongbuild qualities, and relatively low rotational mass. A typicalPowerglide often weighs about 100 pounds (plus or minus 10 pounds,depending on the equipment and whether it has a direct-drive pump or atorque converter).

Comparatively, a three-speed manual Muncie or Saginawtransmission can weigh 30-40 pounds more than a direct-drive Powerglidewhen the flywheel and clutch are included. The high cost of lighteningthose standard transmissions, combined with the expense of a racingclutch, make the Powerglide an economical winner in many cases. Now,with the dummy torque converter, it has gotten even better.