Is there a dyno graph of the Pulley Kit on the WRX?

Yes, we tested an MY97 WRX on the dyno with and without the kit, and you can see that the chart shows significant gains at the bottom and the top of the rev range. The reduction in rotating inertia (we've removed about 2kg by using 6061 T6 aluminium billet) means that the engine can accelerate much quicker during the times it is making very little power before the turbo spools up. The result is better driveability off-boost and better acceleration, which is especially useful for those with large turbos that only make power in the upper rev range. The smaller size of the crank pulley under-drives the power robbing accessories so that the upper end of the rev range is less burdened, while still allowing them to operate properly.

It is difficult to show the true benefit of the kit on the dyno, since the pulleys reduce INERTIA, which by definition is an object's resistance to acceleration. This means that the benefit only comes when the engine is accelerating, much like removing weight from your car. On a dyno the revs are brought up relatively slowly, and the difference is still noticeable. So on the road, a bigger gain is noticed when you accelerate quickly.