Engine

Active filters
- 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.
Includes top and second compression rings plus three-piece oil control rings; supplies enough rings for two pistons for reliable sealing and oil control.
Complete replacement ring set with top and second compression rings plus three-piece oil control rings. Restores compression, controls oil, and improves oil economy. Includes enough rings for two pistons. Made in the USA.
Complete set of top, second, and three-piece oil control rings for two pistons. Barrel face top rings and Napier second rings provide improved sealing and heat transfer; three-piece Flex Vent oil rings ensure positive oil control. Made in the USA.
Complete replacement piston ring set with PVD coating: barrel face top rings, Napier second rings, and three‑piece flex vent oil control rings. Includes enough rings for two pistons.
Forged performance replacement for stock hydraulic roller lifters. 100% tested and made in the U.S.A.
Adjustable front stabilizer link for HD Touring frames with reverse-thread rod end and ARP stainless bolts; available in black anodized, gold anodized, or machined finish. Made in the USA.
Mounts S&S E/G or Keihin CV style air cleaners to Mikuni HSR 42/45 carburetors. Made in the USA.