This Stage IV Kit was designed to deliver maximum horsepower – all the way to the redline. Features new CNC-ported heads with 1mm bigger valves and fully machined combustion chambers. Coupled with the kit's high-lift SE8-517 cam, high compression pistons and a 64mm throttle body and intake manifold, this combination delivers a thrilling 126 ft-lb of torque and 121 HP rear-wheel output when paired with Screamin' Eagle Street Cannon Mufflers. It’s designed to run wide open at high-end RPMs and provide a significant boost of torque from cruising speed. You’ll feel the difference as soon as you twist the throttle. When installed by an authorized Harley-Davidson Dealer within 60 days of the vehicle purchase, compliant kits do not impact the vehicle’s limited warranty. Kit includes: CNC Ported Cylinder Heads with CNC machined chamber and 1mm larger valves L93, Stage IV Timer Cover, SE8-517 High-Lift Cam, Forged High Compression Pistons, High Performance Cam Bearing, Tappets, 4.31" Steel Sleeve Cylinders, 64mm Throttle Body and Cast Manifold and High Flow Injectors (5.5 g/sec).
•Stage IV Kit - 107CI to 128CI for Twin-Cooled models
•Delivers increased response throughout the entire RPM range
•Provides thrilling acceleration when twisting the throttle
•Maintains flat torque curve from cruising RPM to redline
•Can be installed without removing the engine from chassis
•Retains Original Equipment Factory Warranty
Fits '17-later Touring models equipped with Twin-Cooled Milwaukee-Eight 107CI engine. Does not fit Trike models. '17-'19 models require separate purchase of High-Capacity Oil Pump P/N 62400248. '17-'18 Screamin' Eagle High-Capacity Clutch Plate Kit P/N 37000258. All models require ECM recalibration with the Pro Street Tuner for proper installation.
