Wiseco K1617 3.537" Bore 7:1 Compression Domed Forged Piston Kit for Harley-Davidson 80ci Shovelhead

The Wiseco K1617 is a complete forged piston kit designed for Harley-Davidson 80 cubic inch (1340cc) Panhead and Shovelhead V-Twin engines. Featuring a 3.537-inch bore and a 7:1 compression ratio domed piston design, this kit delivers reliable performance and durability for classic Big Twin applications.

Wiseco is the only aftermarket piston manufacturer in the United States that produces pistons exclusively using the forging process. Starting with aerospace-grade aluminum, the forging process increases material density and aligns the grain flow of the alloy, producing a piston that is highly resistant to impact and fatigue — advantages that cast pistons simply cannot match.

Kit Contents:

• 2 forged aluminum domed pistons with coated skirts
• Hastings-style X-Ring package: .062" top ring, .062" compression ring, and .158" oil ring
• Chrome piston pins (wrist pins)
• Retainer circlips

Key Features:

• Aerospace-alloy forgings — superior strength-to-weight ratio versus cast alternatives
• Domed piston design engineered for improved flame travel and combustion efficiency
• Precision skirt geometry — detailed skirt profiles ensure stability and smooth cylinder bore operation
• Coated piston skirts reduce friction and wear during operation
• Optimized installed clearance — engineered for maximum power, minimum wear, and best ring seal at operating temperature
• High-silicone aluminum alloy construction — low thermal expansion for consistent dimensions across operating temperatures
• 3D-designed and FEA-validated — Wiseco engineers use finite element modeling to ensure maximum strength at minimum weight

The K1617 kit is part of Wiseco's V-Twin 4-Stroke Forged Series and cross-references internal part numbers 3537X (piston) and 4729P4. This kit provides everything needed for a complete top-end piston replacement on eligible 80ci Panhead/Shovelhead applications.