This Stage IV Kit was developed to deliver maximum horsepower from the Milwaukee-Eight® engine - all the way to the redline. The system-matched combination of larger displacement cylinders, free flowing CNC-Ported cylinder heads and a cam with the highest available valve lift are the starting point to building the perfect engine for the performance junkie. Designed for a high level of flexibility, this package is ideal for riders who like to comfortably cruise at lower rpm but still have plenty of arm-pulling acceleration when you whack the throttle. Kit includes CNC Ported Cylinder Heads with Performance Valve Springs, 64mm Throttle Body, High Flow Injectors (5.5g/s), 4.075" Bolt-On Cylinders, Forged 11:1 High Compression Aluminum Coated Pistons and Rings, SE8-515 Cam, Cam Bearing Upgrade, High Performance Tappets, Multi-layer Coated Head Gaskets, High Capacity Clutch Springs (1200N), High Capacity Clutch Disks and most necessary gaskets and seals.
...Read MoreFits '18-'20 Softail and '17-'21 Touring models equipped with air/oil cooled 107CI Milwaukee-Eight engine. Does not fit Trike models. Requires separate purchase of Cam Drive Retention Kit P/N 25566-06. Installation may require Cam Spacer Kit P/N 25928-06. For ’17-’18 Touring models, installation of Oil Pump Cover P/N 62400206 is recommended (sold separately). All models require ECM calibration with Screamin' Eagle Pro Street Tuner or dealership installed Screamin’ Eagle calibration for proper installation. Pending approval for use in California on '21 models. Refer to H-D.com/shop for status.