Wiseco SK1331 Forged Piston Kit for Arctic Cat Snowmobile - 66.50mm 2-Stroke

The Wiseco SK1331 is a high-performance 66.50mm 2-stroke forged piston kit engineered specifically for Arctic Cat snowmobiles. Developed for the rigorous demands of snocross and cross-country racing, this piston kit delivers the strength, durability, and precision that serious riders depend on.

Wiseco is the only aftermarket piston manufacturer in the United States that produces pistons exclusively using the forging process. Starting with aerospace-grade, high-silicon aluminum alloy, the forging process compresses the material's molecules—increasing aluminum density and aligning grain flow. The result is a piston with superior resistance to impact and fatigue, and improved ultimate strength and ductility compared to conventional cast alternatives.

Key Features:

• 66.50mm bore diameter — precision-engineered for a direct fit
• Forged construction — aerospace-grade aluminum for maximum strength-to-weight ratio
• Condensed, aligned grain structure — resists catastrophic failure under extreme load and heat
• Skirt coating — factory-applied coating for reduced friction and improved break-in
• USA forged and manufactured — Wiseco produces all pistons and forge tooling in-house domestically
• 3D design and finite element modeling — every piston design is engineered for optimal strength and minimum weight
• In-house dyno validated — developed and tested at Wiseco's state-of-the-art facility
• Kit includes: piston, rings, wrist pin, and circlips

Unlike cast pistons, which are brittle and prone to catastrophic failure when yield strength is exceeded, Wiseco forgings feature a condensed grain structure aligned to the geometry of the part—producing higher mechanical properties and far greater resistance to the shock and fatigue loads common in high-performance snowmobile engines. The SK1331 piston kit is the trusted choice for Arctic Cat snowmobile riders who demand race-proven performance and long-term reliability.