Beef Up A PowerGlide With An ATI Torsional Input Shaft

PowerGlide transmissions got a bad rap in the ’70s for being too weak to handle big horsepower. Once muscle car fanatics and racers figured out that the weak-kneed transmission became a super hero with the swapping out of a couple of parts, the PowerGlide became the weapon of choice on the strip. 

One of the weak areas that was immediately identified was the input shaft. The shaft was designed to sheer before damage to internal components could happen. The sheer shaft worked and that was part of the problem… it worked too well. The OEM shafts snapped whenever any real power was applied. Almost overnight a slew of hardened input shafts hit the market and helped to solve the issue. ATI Racing has now taken the design another level with their Torsional input shaft.

According to the experts at ATI, “The Torsional Input Shaft works like a torsional spring bar, twisting and returning to totally eliminate breakage while reducing shock loads to the gear train.” In plain speak, the shaft will “give” and “return” without breaking. They are designed to fit either the Powerglide or TH400 splines and the shafts are available for V8 and 6-cylinder carriers.

In addition to their precision-machined torsional shafts for PowerGlide, Turbo Hydromatic 350 & Turbo Hydromatic 400, ATI also offers special extreme-duty models for the PowerGlide and Turbo Hydromatic 400 made of Vasco steel. An exceptionally strong material that is resilient enough to withstand the severe torsional shocks.

ATI’s “Super Shaft” (Part #207148 & #207149) is a ringless PowerGlide input shaft that still provides the OEM lube circuit to properly lubricate your transmission and maintain proper converter charge pressure for performance. Machined from 315,000 PSI tensile strength steel alloy in full 1″ diameter, it must be installed with a special stator support tube.

For more information on this and ATI Racing’s other fine products, visit them online at www.atiracing.com