Harley-Davidson's New Screamin' Eagle Milwaukee-Eight Stage IV Kit

Show the Milwaukee-Eight some love by boosting its horsepower up to a claimed 52 percent over stock and gain torque with the new Screamin' Eagle Milwaukee-Eight Stage IV Kit from Harley-Davidson.

This new engine product in the H-D shop was developed to deliver maximum horsepower from the Milwaukee-Eight engine all the way to redline and delivers a boost in both displacement and air flow through the engine.

“We’ve designed this amazing Screamin’ Eagle Stage IV kit for the performance fanatic,” said Harley-Davidson Senior Product Manager Scott Miller. “Big-bore cylinders, a monster throttle body, ported heads, and a high-lift cam combine to deliver stump-pulling torque throughout the rpm range and up to 52 percent more power than the stock Milwaukee-Eight engine.

“The Screamin’ Eagle Milwaukee-Eight Stage IV Kit is a system-matched collection of components created by the same Harley-Davidson engineering team that designed and developed the Milwaukee-Eight engine,” said Miller. “Upgrading the engine with genuine H-D parts supports a performance gain without sacrificing warranty, drivability or reliability. There are no compromises.”

Screamin’ Eagle Milwaukee-Eight ported cylinder heads are a key component of the Screamin’ Eagle Milwaukee-Eight Stage IV Kit. Based on a unique Screamin' Eagle casting, these cylinder heads optimize air/fuel flow when paired with a Screamin’ Eagle 64mm throttle body.

The ports are meticulously machined on a five-axis CNC machine to increase the volume and velocity of the intake charge for improved efficiency of cylinder filling and to maximize the effect of exhaust scavenging. The Screamin' Eagle ported heads are equipped with high-performance valve springs that remain stable with high-lift cams in high-RPM operation. The SE8-515 camshaft, designed in conjunction with the Screamin' Eagle Milwaukee-Eight Stage IV Kit, offers a high-lift and long-duration profile to efficiently fill the combustion chamber and retain 50-state street-legal emissions compliance. Screamin' Eagle 4.075-inch bore bolt-on cylinders and matching pistons increase displacement of Milwaukee-Eight 107 engines to 114 cubic inches, and take Milwaukee-Eight 114 engines to 117 cubic inches. The Screamin' Eagle Milwaukee-Eight Stage IV Kit can be installed without removing the engine from the chassis.

Complete Screamin’ Eagle Milwaukee-Eight Stage IV Kit components include:

There are three Screamin' Eagle Milwaukee-Eight Stage IV Kit options available:

Screamin' Eagle Milwaukee-Eight Stage IV Kit (P/N 92500062 Black Highlighted, MSRP: $2,595.95) fits 2017-later Touring models equipped with air/oil cooled Milwaukee-Eight 107 engine.

Screamin' Eagle Milwaukee-Eight Stage IV Kit (P/N 92500060 Black Highlighted, MSRP: $2,595.95) fits 2017-later Touring models equipped with a Twin-Cooled Milwaukee-Eight 107 engine.

Screamin' Eagle Milwaukee-Eight Stage IV Kit (P/N 92500064 Black Granite Highlighted, MSRP: $2,595.95) fits 2017-later CVO Touring models equipped with a Twin-Cooled Milwaukee-Eight 114 engine.

Pair your Screamin’ Eagle Stage IV Kit with these Milwaukee-Eight Upgrades.