S&s Cycle 129" Power Package Engine Performance Kit for 107" M8

Unleash the full potential of your Harley-Davidson Milwaukee-Eight engine with the S&S Cycle 129" Power Package Engine Performance Kit. This comprehensive bolt-on upgrade transforms your 107" M8 into a formidable 129" powerhouse, delivering significant gains in horsepower and torque without requiring any case machining.

Description

Engineered for motorcycle enthusiasts seeking a substantial performance boost, the S&S Cycle 129" Power Package Engine Kit provides everything needed for a dramatic displacement increase. At its core are big bore 4.320" cylinders paired with high-strength 11.0:1 forged pistons, meticulously designed for optimal combustion and durability. This kit includes the advanced S&S oil pump/cam plate, which features independent scavenge sections for both the flywheel cavity and cam chest, ensuring superior oil management. Integrated debris screens in both scavenge pickups and a magnet in the cam chest actively prevent contaminants from entering the oil pump, extending engine life. With increased oil flow capacity on both the feed and scavenge sides, and an adjustable pressure relief valve that can be serviced while installed, your engine's lubrication system is optimized for extreme conditions.

Further enhancing performance are the Quickee pushrods with black pushrod tubes, S&S premium tappets, and billet aluminum hard anodized, black coated tappet cuffs. The included S&S valve springs are high-performance conical single wire springs, designed to work seamlessly with cams up to 0.605" lift. The heart of this 129" M8 engine kit's aggressive power delivery is the HPT496 cam, specifically engineered for big bore applications. An MLS (multi-layered steel) head gasket ensures a robust seal. Proudly made in the USA, this kit retains your stock engine height, works with stock crankcases and roller rocker arms, and preserves original engine serial numbers, making it a professional-grade upgrade that fits like factory. It's also compatible with both first and second-generation stock valve springs.

Features & Highlights

• Transformative Big Bore Upgrade: Effortlessly convert your 107" Milwaukee-Eight engine to a potent 129" displacement with this bolt-on kit, eliminating the need for complex and costly case machining.
• Optimized Power & Durability: Features precision-engineered 4.320" big bore cylinders and robust 11.0:1 forged pistons, providing exceptional power gains and long-term reliability for your Harley-Davidson M8 big bore kit.
• Advanced Oil Management System: The S&S oil pump/cam plate boasts independent scavenge sections, debris screens, and a cam chest magnet, ensuring superior lubrication, contaminant removal, and increased oil flow capacity for peak engine health.
• Performance-Ready Valvetrain: Includes Quickee pushrods, S&S premium tappets with billet aluminum cuffs, and high-performance conical valve springs compatible with cams up to 0.605" lift for precise and durable valve control.
• Big Bore Specific HPT496 Cam: Experience aggressive power delivery and optimized performance thanks to the HPT496 cam, meticulously designed to complement the increased displacement of this 129" M8 engine kit.
• Seamless Integration & Quality: Made in the USA, this kit retains stock engine height, works with stock crankcases and roller rocker arms, and includes an MLS head gasket for a perfect fit and professional finish, complete with a 129 cam cover badge.

Technical Specifications

• Type: Engine Performance Kit
• Product Name: Power Package
• Style: HPT496 Series
• Units: Kit
• Bore Size: 4.320"
• Displacement: 129"
• Compression Ratio: 11.0:1
• Cam Drive Type: Chain
• Cooling System: Oil Cooled
• Color/Finish: Black, Highlighted Fins
• Features: Black Pushrod Tubes
• Vendor Part Number: 310-1395