Take your Harley Big Twin build to the next level with this matched pair of raw, high-flow cylinder head blanks designed specifically for 1984–1999 Harley-Davidson Evolution 1340 engines. Engineered as premium-grade castings, these heads serve as the ultimate foundation for custom engine builders, porters, and tuners looking to unlock maximum horsepower and torque from an Evo platform.

​Key Features & Design Elements:

• ​Unrestricted Customization: Supplied as raw/semi-finished high-flow blanks, allowing professional porters to shape the combustion chambers, optimize port volumes, and tailor flow velocities for high-compression stock rebuilds, large displacement strokers, or race applications.

• ​Cast Aluminum Construction: High-density aluminum casting offers superior thermal conductivity and structural integrity, built to handle extreme combustion pressures and high-lift cam profiles.

• ​Component Readiness: Designed to accept upgraded bronze valve guides, custom-machined valve seats, oversized stainless steel valves, and heavy-duty high-lift valve spring packages.

• ​Cooling Fin Layout: Retains the classic Evo fin architecture while providing extra meat in critical areas for heavy-duty porting without breaking through the casting walls