Kartboy has released their rear subframe inserts for the 2008-2014 WRX. These will be inserted into the subframe voids in the OEM bushings of the 08+ impresa models. These are going to reduce subframe shock, and will increase the feedback on the rear suspension.
These Kartboy rear subframe inserts will also improve and stabilize the rear suspension geometry. Hand made in the U.S.A., and 100% guaranteed.