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Upgrade your Harley-Davidson M8 engine with the S&S Cycle 129" Power Package Engine Performance Kit. Designed to expand your engine's displacement from 107 inches to 129 inches without the need for case machining, this kit offers a straightforward solution for increased power and performance. The big bore cylinders come complete with a matching cam, cam plate, and oil pump, ensuring seamless integration and reliable operation. The kit is compatible with stock crankcases, making installation more accessible for enthusiasts and professional mechanics alike. Constructed with high-quality materials, this performance package maintains the original engine serial numbers, ensuring compliance with regulations and easy identification.
The design features independent scavenge sections for the flywheel cavity and cam chest, optimizing oil flow and engine cooling. A magnet integrated into the cam chest helps prevent debris from entering the oil pump, extending engine longevity. The kit includes high-performance conical single-wire S&S valve springs, which provide improved valve control and durability under high-stress conditions. Passage plugs are removable for servicing, allowing for easy maintenance and inspection. Both scavenge pickups are equipped with debris screens, further protecting the engine’s vital components. Multi-layered steel (MLS) head gaskets ensure a reliable seal under increased pressure, supporting the engine's enhanced performance. The 550 cam is specifically matched to optimize power delivery and throttle response, making this kit ideal for riders seeking a significant upgrade in horsepower and torque. Made in the USA, the S&S Cycle 129" Power Package Engine Performance Kit delivers quality, durability, and performance for your M8 engine, whether you're building a custom bike or upgrading for daily riding.
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US Dollars
