WP550 (M8)

Metal camshaft with multiple lobes on a black background.

Description:

  • Meet the horsepower benchmark. The WP550-M8 Harley-Davidson Milwaukee-Eight camshaft is our original big-bore weapon, built for 124–132 cu in engines running 11.5-to-12:1 compression. A savage idle tells the story; crack 3,000 RPM and it pulls hard to 6,500 RPM, posting 170-plus HP with the right intake and exhaust. Street manners below 2,500 RPM stay intact, but this is not a bolt-in swap—plan on upgraded springs, pushrods, and a pro tune to let the cam breathe and dominate.

Key Features & Rider Benefits:

  • High Horsepower Focus: Specifically designed to produce very good mid to high RPM horsepower.

  • Aggressive Sound & Performance: Delivers an awesome aggressive lope at idle and a strong pull from 3000 to 6500 RPM.

  • Streetable Manners: Impressively maintains good drivability and low RPM manners despite its aggressive nature.

  • Durability by Design: Features a .550" valve lift for great valve train durability.

  • Beat Your Buddy: This cam was engineered to give you the edge and make serious numbers.

    • Effective RPM Range: 2500 - 6500 RPM

    • Recommended Engine Displacements: Designed for 124" to 132" big bore M8 engines.

    • Ideal Rider: The rider who wants to make the number and beat their buddy; perfect for aggressive street performance in big bore builds.

    • Valve Lift (Intake & Exhaust): .550" / .550"

    • Effective RPM Range: 2500 - 6500 RPM

    • Recommended Engine Displacements: 124" to 132" big bores with 11.5:1 or more compression.

    • Intake Closes (ABDC @ .050"): 48 degrees

    • Exhaust Closes (ATDC @ .050"): 11 degrees

    • Intake Duration (@ .050" lift): 242 degrees

    • Exhaust Duration (@ .050" lift): 254 degrees

    • Overlap (@ .050" lift): 25 degrees

    • Lobe Separation Angle (LSA): 111.5 degrees

    • Intake TDC Lift (@ TDC): .146"

    • Exhaust TDC Lift (@ TDC): .124"

    • Recommended Static Compression Ratio(s): 11.5:1 or more (12:1 being optimum for pump gas).

    • This is NOT a bolt-in camshaft.

    • Valve Springs: Requires Upgraded Valve Springs.

    • Pushrods: Requires Adjustable Pushrods.

    • Lifters: Performance Lifters Recommended.

    • Throttle Body: Recommend to Upgrade.

    • Intake Manifold: Recommend to Upgrade.

    • Exhaust System: Performance Exhaust Recommended.

    • Air Cleaner: High Flow Air Cleaner Recommended.

    • Engine Tuning: A Full Professional Tune Recommended for Optimal Performance.

    • Pistons: Requires high performance / specific compression piston kit to achieve recommended compression ratios.

    • Oiling System: Compatible with stock components.

    Critical Notes:

    • Recommend 124 or greater big bore kits with added compression ratio of at least 11.5:1, with 12:1 being optimum.

    • Not for use with VVT equipped engines.

    • Compatible with Harley-Davidson 2017 to current M8 engines.

    • Excludes VVT models.

    • Made in the USA.

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