Vivid Racing just finished testing the Agency Power crank pulley on the 2008 Subaru WRX. The lightweight crank pulley is the same diameter as the stock unit. Saving several pounds of rotating weight, the pulley is designed to increase throttle response while gaining performance. The pulley fits on with no issues to the 2008 except the change in the AC belt tensioner. The new 2008 does not have a tensioner, so once you remove the stock belt or cut it, you are unable to get a new one on. Putting a new belt on requires a special tool from Subaru.
However, all mounts are in place to run the factory tensioner that was on the 02-07 cars. With about $60 in extra parts including a new belt, you are good to go again. Down the road we anticipate the special tool from Subaru or we may supply an aftermarket part instead of using the OEM tensioner.
To mount the tensioner on the car, the following Subaru part numbers are required –
73131FC000 – Tensioner Pulley Part
73134AC001 – Tensioner Pulley Part
73132AC000 – Long Bolt
73610AC000 – Bracket
In the mean time, the crank pulley was dyno tested on our Mustang ALL Wheel Drive Dyno. The pulley as test added 6 wheel horsepower and 9 ft/lbs of torque to the car.
