S&S Cycle 106-3255 Super Stock 89cc Cylinder Head Kit Silver Powder-Coat

The S&S Cycle Super Stock 89cc Cylinder Head Kit (106-3255) is a high-performance replacement head kit featuring a silver powder-coat finish, designed to deliver serious airflow gains and improved power output over stock cylinder heads. Fully assembled with valves and springs, this kit is a straightforward upgrade for Big Twin engines running larger displacements.

The 89cc combustion chamber delivers a slightly higher-than-stock compression ratio that remains manageable in larger-than-stock engines, making it an excellent choice for touring bikes and heavier platforms. These heads work well with engines of stock displacement, but are ideal for stroker or big bore engines up to 110 cubic inches.

Key Features:

• 89cc combustion chamber — provides a slightly elevated, manageable compression ratio for larger displacement engines
• 2.000" intake valves and 1.605" exhaust valves — sized to maintain port velocity for strong low and midrange response while supporting higher-displacement builds
• 264 cfm intake port flow — a major improvement over the stock 182 cfm rating
• High-performance valve springs — supports camshaft installations with up to .650" lift
• Silver powder-coat finish — durable, corrosion-resistant finish matches stock engine aesthetics
• Fully assembled — heads ship complete with springs and valves, ready to install
• Machined for compression releases — compatible with S&S electric or manual compression releases (sold separately); S&S rocker boxes (Part #90-4110) required when compression releases are used
• Includes four long head bolts — reuses four long OEM head bolts; does not include rocker arm components, intake manifold, or gaskets
• Compatible with stock rocker boxes, exhaust, and intake manifolds when compression releases are not used
• Made in the U.S.A.
• Not compatible with Twin Cooled models

Best suited for engines over 103" or builds using high-compression pop-up pistons, the S&S Super Stock 89cc heads are a proven performance upgrade that pairs well with S&S cams, big bore kits, and other top-end modifications.