Stock-height long-block replacement for Evolution engines. Includes performance heads, pistons, valve springs and a 508 camshaft. EFI compatible; fuel/ignition sold separately.
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Carbureted V80 assembled engine that fits stock '84–'99 Evolution Big Twin frames; upgraded S&S carburetor, cam, heads, and single-fire ignition.
Bolt-on performance kit with bolt-in cams and premium tappets. Easy installation with no machining or rebalancing. Uses stock heads, pushrods, and fuel system.
Complete bolt-on big-bore kit that raises displacement without case machining. Includes cylinders, forged pistons, upgraded oil pump/cam plate, valvetrain hardware, and all gaskets and bearings for installation.
- Bolt-on power: +40–50% on stock 107", 114" and 117" M‑Eight motors.
- Compressor and turbine housing with Garrett internals; plenum with integrated blow-off valve.
- Includes injectors, spark plugs, boost gauge with mount, oil feed/drain lines, custom cam cover, tune files, hardware and gaskets.
- Requires Thundermax ECM (sold separately). Does not fit Twin Cooled or non-removable fairing lowers. Offroad use only.
- Made in the USA.
Complete 132" engine performance kit converts 114"/117" oil-cooled M8 to 132" with big-bore cylinders, performance-matched 550 cam, adjustable relief valve, and serviceable components.
Complete kit to convert 114" or 117" oil-cooled M8 engines to 132" displacement while retaining stock height and serial numbers. Includes adjustable pressure relief valve, S&S valve springs, big-bore cylinders, MLS head gaskets and a performance-matched 550 cam.