S&S 129" M8 Big Bore Power Pack for Harley Milwaukee 8 107"

Upgrade your ride with the ultimate performance transformation for your Milwaukee-Eight engine. This comprehensive Big Bore Power Pack is designed to deliver a massive increase in displacement and torque without compromising the integrity of your motorcycle’s original configuration. Engineered for seamless integration, this kit provides a significant power boost while maintaining the reliability and longevity expected from industry-leading performance experts.

Whether your engine is oil-cooled or water-cooled, this system is precision-engineered to work within the parameters of your stock crankcases and maintains the original engine height for a perfect fit. The high-quality powder coat finish is specifically formulated to match your factory engine aesthetics, ensuring that while the power is legendary, the look remains clean and integrated. Additionally, the design allows owners to retain their original engine serial numbers, preserving the identity of the bike.

Features & Benefits

• Big-bore bolt-on kit increases 107" M8 to 129" with no case machining required
• 4.32" bore cylinders with 11.0:1 compression ratio forged pistons
• S&S oil pump/cam plate with blue anodized finish
• Passage plugs are removable for servicing
• Independent scavenge sections for flywheel cavity and cam chest
• Debris screen in both scavenge pickups
• Magnet in cam chest to help prevent debris from entering the oil pump
• Increased oil flow capacity on both the oil feed and scavenge side
• Adjustable pressure relief valve can be adjusted with the unit installed in the engine
• Quickee pushrods
• S&S premium tappets
• S&S hard-anodized, black coated tappet cuffs are billet aluminum construction
• S&S 550 cams are designed for big bore applications
• S&S valve springs work with cams up to 0.605" lift
• High-performance conical single wire spring design
• All necessary gaskets, bearings and hardware for bolt on installation included
• Made in the USA
  

This all-in-one power solution includes all necessary components to revitalize your engine’s performance, including high-flow cylinders and precision-engineered valvetrain components. By choosing this unified Power Pack, you are investing in a proven performance pedigree that balances extreme power with everyday rideability.

2017-2023 Harley M8 Models w/ 107 Oil Cooled Motor