In high gear, the only transmission parts that rotate are: the input shaft, five 2 3/4 diameter driving clutch disc, two small dog clutches, and the output shaft. None of the gears or other internal components rotates. That provides for the absolute minimum rotating inertia.

Brinn's design has resulted in an assembly that has the absolute lowest rotating assembly inertia of any transmission, and that reduced inertia results in faster acceleration. The entire high-gear rotating assembly weighs only 11 pounds and has a maximum diameter of 2 3/4 inches - and only the driving clutch discs are that big. Everything else is smaller still.

As revolutionary as his design was a year ago, Brinn was already thinking about improving it. The latest generation features the same internal components used in the prototype, but the magnesium case has been redesigned. It is now more compact; the distance between the center line of the input shaft and the bottom of the transmission's case is only 4 1/4 inches. To appreciate just how low that is, consider that the distance between the crankshaft center line of a stock-stroke small block Chevy and the outer surfaces of the rods' big ends is about 3 3/4 inches. With a four-inch-deep oil pan, the bottom of the transmission and the engine's connecting rods are within 1/4 inch of the same ground clearance.

While this transmission will bolt directly to a stock Chevy bell housing, Brinn also offers cast magnesium bell housings that allow the minimum ground clearance and also provide for driving a dry-sump oil pan on the left side. When combined with dry-sump oil pans that have left-side outlets, this bell housing arrangement allows for very short and straight oil scavenge lines.

Brinn calls his newest transmission the Pro-Series because it is targeted at higher-end racers who are looking for that little extra performance and are willing to pay for it. At roughly $3000 racer-net, Pro-Series transmissions are not intended to replace the original, older internal-clutch Brinn transmissions, but they do offer a clear advantage over everything else on the market.

The new Pro-Series transmissions are available through Brinn distributors nationwide.