300M ALLOY INPUT SHAFT, TURBO SPLINE, 12-5/8" (FITS 1.82, 1.90, 1.94, 1.98, 2.08)

The Coan Racing COA‑12803 300M Alloy Input Shaft (Turbo Spline, 12-5/8″) is a high-performance component engineered for GM Powerglide transmissions configured with turbo-style splined torque converters and low-gear ratios of 1.82, 1.90, 1.94, 1.98, and 2.08. Crafted from robust 300M alloy, this shaft offers substantial tensile strength and fatigue resistance, making it ideal for high-torque street and racing applications. It fits directly into cases tuned to the specified gear ratios without requiring machining or modifications, delivering a seamless upgrade path.

The precision-machined turbo spline design ensures consistent engagement with the torque converter, while the durable alloy construction provides long-term reliability under extreme conditions, making the COA‑12803 an excellent choice for builders seeking enhanced drivetrain strength and dependable performance.