The other day I installed my new Agency Power crank pulley. Compared to the stock pulley it is alot lighter. The fit and finish is great. Installing the new pulley took only half an hour with no problems. As far as performance gains, everything seems a little quicker now. The engine revs faster, and the car seems to accelerate faster. Also the car seems to pull a little harder at high rpms. For the cost i would definitely recommend this upgrade.