ATI's Super Damper for Subaru EJ20, EJ22 and EJ25 engines - Part # 917991. Unlike undampened underdrive pulleys, which offer no protection to high performance engines, the ATI Super Damper provides balanced dampening of torsional crankshaft vibrations at all RPM levels. The ATI Super Damper comes with laser-etched timing marks and is a direct replacement for the OEM unit. The ATI Super Damper is a critical component for all high performance cars to help protect against engine harmonics and features four-groove and five-groove serpentine belt drives on the outer shell to utilize the factory serpentine belt set-up. All ATI Super Dampers exceed SFI 18.1 Safety Certification and are approved for competition use.

Provides balanced dampening of torsional crankshaft vibrations at all RPM levels

Engine: EJ
O.D.: 5.5"
Ribs: 5 & 4

Shell Material: Aluminum