What was stock on a 96 WRX?.. if it was 205/55/16 this guide must be out with my new fitment of 215/45/17 cos when my speedo says 1m doing 80 my sat nav says im doing 70 and so on even checked against them signs that tell you on road if your speeding and my cars quite a lot out at 30... back on the 16" alloys i used to be about 4mph out..