S&S CYCLE 129" Power Package Engine Performance Kit for M8 - Chain Drive Oil Cooled with Highlighted Fins (Part No. 310-1223)

S&S CYCLE

S&S CYCLE 129" Power Package Engine Performance Kit for M8 - Chain Drive Oil Cooled with Highlighted Fins (Part No. 310-1223)

Product type: Big Bore Kits

Vendor: S&S CYCLE

SKU : 0904-0100

Regular price $3,359.95 USD

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129" Power Package Engine Performance Kit - Chain Drive - Oil Cooled - Highlighted Fins - M8 Upgrade your Harley-Davidson M8 engine...

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129" Power Package Engine Performance Kit - Chain Drive - Oil Cooled - Highlighted Fins - M8

Upgrade your Harley-Davidson M8 engine with the S&S CYCLE 129" Power Package Engine Performance Kit, designed for optimal performance and durability. This kit transforms your 107" oil-cooled M8 into a powerful 129" engine without the need for case machining, making it an ideal choice for riders seeking significant upgrade potential. The kit includes big bore cylinders that come with matching cam, cam plate, and oil pump, ensuring seamless compatibility and reliable operation. Its independent scavenge sections for the flywheel cavity and cam chest help optimize oil flow and reduce maintenance concerns. A magnet in the cam chest acts as a debris trap to prevent contaminants from entering the oil pump, extending engine life and reducing wear.
Features include high-performance conical single-wire S&S valve springs that improve valve control at high RPM, enhancing overall engine responsiveness. The kit retains original engine serial numbers, which is important for registration and warranty purposes, and features removable passage plugs for easy servicing. Debris screens in both scavenge pickups further protect the oil system from contaminants. Multi-layered steel (MLS) head gaskets ensure a reliable seal under high-pressure conditions, maintaining optimal compression and performance. The included performance-matched 550 cam provides a significant boost in power and torque, delivering a more aggressive riding experience. Designed to work seamlessly with the stock crankcase, this kit offers an upgrade path without the need for extensive modifications. Made in the USA, the S&S CYCLE 129" Power Package Engine Performance Kit combines quality craftsmanship with performance enhancements, making it a top choice for serious Harley enthusiasts seeking increased power and reliable operation.

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