The JE pistons are also lightweight by design, tipping the scales at a mere 330 grams. In this case, the PN 923FL pistons were actually designed for common roundy-round "claimer" engines, and that makes them affordable, too. The simple flat-top design also boasts deep cavities under the outer deck surface to lose more precious grams (arrows). The piston pin is also lighter than factory designs, but it maintains the factory .927-inch diameter. It loses weight in length, as it's 2.3-inches long versus the factory 2.5-inch length.