Milwaukee-Eight Engine Stage IV Kit - 114/117CI to 131CIGo big or go home. With the largest displacement of any Harley Davidson Stage Kit, this 114 117CI to 131CI Stage IV Kit is designed to deliver maximum horsepower all the way to the redline. Packaged with patent protected cylinder technology, it allows for the largest bolt on engine upgrade to any Milwaukee Eight motor. Features new CNC ported heads with 1mm bigger valves and fully machined combustion chambers. Coupled with the kit's high lift SE8 517