Wiseco Hi-Performance Small Block Chevrolet Pistons feature 1/16" x 1/16" x 3/16" ring grooves. Supplied with chrome moly wrist pins and spiro lox. Recommended pistion to wall clearance is . 004", measured at 1. 300" below the oil ring groove. Fits 23 degree cylinder head. Factory Deck Height is 9. 025" from centerline of crank to top of cylinder case.Pit Stop USA offers Wiseco Hi-Performance Piston Set - SB Chevy - 4.155" Bore Size, 3.875" Stroke, 6.000" Rod Length K071A3 at low everyday prices. Be sure to check out all of our products from Wiseco including Wiseco Forged Pistons - Small Block Chevy.