300M Ringless Alloy Input Shaft, 12-7/8" - Turbo Splines

300M RINGLESS ALLOY INPUT SHAFT, TURBO SPLINES, 12-7/8" FITS 1.69, 1.76, 1.80, 1.89, 1.96, 2.03

(REQUIRES COA-12814, 12815, 12816A, 12816B PUMP)

The Coan Racing COA‑12806 300M Ringless Alloy Input Shaft (Turbo Splines, 12-7/8″) is a premium drivetrain upgrade engineered for GM Powerglide transmissions utilizing turbo-spline torque converters across a range of low-gear ratios (1.69 to 2.03). Constructed from high-strength 300M alloy, this robust shaft delivers exceptional tensile strength and fatigue resistance to handle the rigors of high-horsepower applications. Its innovative ringless design features mid-shaft bushing journals, eliminating the need for ring-type input shafts and enabling compatibility with cooling circuit-equipped pumps, while significantly reducing flex under load.

The COA‑12806 installs cleanly into cases calibrated for the specified ratios. It does require pairing with Coan’s pumps (COA‑12814, 12815, 12816A/B) to ensure proper pump interfacing, but it offers a seamless, high-strength drop-in solution for racers and performance builders seeking enhanced durability, cooling capability, and drivetrain confidence.