Wiseco K473M965 Forged Piston Set GM LS 5.3L 3.800 Bore -7cc Dish 10.25:1

The Wiseco K473M965 is a Professional Series forged piston set engineered for GM LS / Vortec 5.3L engines. Forged from 2618 high-strength aluminum alloy and manufactured in the USA, these pistons deliver superior tensile strength and fatigue resistance over cast alternatives, making them an ideal choice for naturally aspirated and nitrous-assisted street and race builds.

Each piston features a -7cc dish crown designed with LS1/LS2/LS6 valve pockets to accommodate the factory valvetrain geometry while delivering a 10.25:1 compression ratio with a 62cc combustion chamber. The piston skirts are treated with Wiseco's proprietary ArmorGlide® coating, which reduces friction, allows for tighter bore fitment, and improves wear resistance over the life of the engine.

Key Specifications:

• Bore: 3.800 in.
• Compression Height: 1.110 in.
• Pin Diameter: 0.927 in. (Pin Kit S643, 0.927 x 2.250 included)
• Pin Wall Thickness: 0.150 in. with Spirolox® retainers
• Stroke: 4.000 in.
• Rod Length: 6.125 in. (designed for aftermarket connecting rod)
• Crown Volume: -7cc (dish)
• Compression Ratio: 10.8:1 @ 58cc / 10.3:1 @ 62cc / 9.8:1 @ 66cc / 9.5:1 @ 70cc
• Piston Weight: 376 g per piston
• Alloy: 2618 high-strength aluminum
• Valve Pockets: LS1, LS2, LS6 compatible
• Ring Grooves: 1/16 in. x 1/16 in. x 3.0mm (rings sold separately — recommended ringset: 3805HF)
• Application: GM LS / SBC LS1 / Vortec 5.3L — NA and Nitrous

Features:

• ArmorGlide® skirt coating for reduced friction and improved ring seal
• Anti-detonation and pressure seal grooves for enhanced combustion control
• 2618 alloy construction forged and machined in the USA
• 0.150 in. wall wrist pin with Spirolox® retainers included
• Designed for use with aftermarket connecting rods
• LS1/LS2/LS6 valve pocket geometry

Rings are sold separately. The recommended ring set for this application is Wiseco part number 3805HF. This is a shelf-stock kit ready for immediate installation in standard or mildly built 5.3L LS engine combinations.