The Sonnax 10-clutch system increases lockup surface in GM Powerglides for significantly more torque capacity than modified OE drums. The drum and piston accept 10 .060" frictions and 10 .060" thick increasing lockup surface to allow significantly more torque than modified OE drums.
Sonnax 10-clutch drum, hub and piston kit 28756-15K includes the three essential components for building a 10-clutch drum assembly. An alternative kit, 28756-16K, includes a pump-to-drum bearing.
I've used several of the Powerglide 10-clutch drum kits in drag racing performance builds. The quality and reasonably priced product makes the choice to use over a stock or reconditioned drum a no-brainer.G. Carson