2-Dual Ring Pistons
2-Ring Sets
2-Wrist Pins
4-Circlips
2-Wrist Pin Bearings
1-Gasket Set

SPI pistons are engineered to provide the best possible path for combustion chamber heat transfer to the cylinder walls
All SPI pistons, rings, pins, & circlips are manufactured to OEM specifications
All individual components are interchangeable with original parts
Piston weight is compatible with original piston
T-Moly series with Teflon-Molybdenum coating
T-Moly series pistons reduce friction, resist seizure, & improve durability
Made in Taiwan
72 mm STD Bore

1986, 1987, 1988 Ski-Doo Formula Plus 521 (537 Engine Type)









INTERNATIONAL BUYERS: Our shipping fees do not include any duties, taxes, or brokerage fees. You are responsible for ALL fees. 

Photo Above is Universal