Brinn Transmission Kit for 1 Piece Rear Main Seal

Built for 1986-and-later Small Block Chevrolet engines with a 1-piece rear main seal, this Brinn kit targets oval and dirt track classes such as Wissota Modified, IMCA Modified, Sport Mod, and Hobby Stock, sold for competition rather than street driving.

What the transmission itself offers

An internal dog-clutch design does away with the usual outboard clutch and throwout bearing, trimming drivetrain weight and upkeep, while cryogenically treated internals sit inside a lightweight aluminum case. Ten splines on a 1.0625-inch input shaft feed 27 splines on a 1.375-inch output riding a slip-on yoke, geared 1.88:1 low, direct 1:1 high, and 2.29:1 reverse, rated to 600 lb-ft of torque.

What the kit adds around it

A heavy-duty steel bellhousing comes with it, drilled to both Small Block Chevy and Small Block Ford patterns, laser-cut and CNC-machined so it also lines up with Muncie and Saginaw patterns shared by Brinn, Bert, and Falcon gearboxes. Rounding out the kit: a steel drive flange sized to the 1-piece seal, crankshaft bolts, a 60-inch brake line with a straight adapter fitting, performance fluid, a storage stand, and mounting hardware.

Brinn backs it with a 3-year limited warranty on materials and workmanship for competition use that is properly installed and maintained, longer coverage than most of Brinn's other racing gearboxes carry.