Fits on EJ Series Engines Decreases rotational mass more than 3.5lbs over OEM (You will see much faster revs as a result) Factory Fit for clean install Optimum weight to avoid misfire CELs or hesitation 2008+ OEM Subaru Stretch Belt Install Kit Option (No other company offers this Optional Add-On) Balanced CNC machined 6061 T6 anodized Aluminum Includes OEM timing marks for timing ...
Your factory crank pulley is responsible for transferring energy from your crankshaft to your water pump, a/c compressor and alternator. It does this by way of a rubber belt and it does it's job well. The drawback to the factory pulley is that it's quite heavy. Reasons for this include less expensive manufacturing and using the pulley's mass to smooth out 'noise' in the accessory system (NOT to ...