106-5780 3-7/16" forged stroker piston kit. +.070"

This S&S forged piston kit is engineered for 1941 to 1984 Big Twin engines, covering Knucklehead, Panhead, and Shovelhead models. These +.070 over pistons are designed for stroker applications, specifically 84-inch, 86-inch, and 88-inch engines using stock 5.330-inch length cylinders. The advanced alloy construction and specialized skirt profile ensure a long service life with minimal mechanical noise. With a 50cc dome volume, these pistons provide approximately 8.4:1 compression with a 4-1/2 inch stroke, rising to 10.8:1 with a 4-3/4 inch stroke. Sold as a set, the kit comes complete with forged pistons, wrist pins, clips, and rings. It is a professional-grade choice for riders looking to maximize displacement and reliability in their vintage Big Twin power plant.