What you're about to see isn't your standard balls to the wall, all out race to the top like many other hill climb events. Instead, in this particular Targa, the run up the Crown Range Pass - a public road that climbs to 1,100 meters above sea level by the way of fast twisty corners and steep uphill hairpins - the rules operate more like a stage rally.
Gavin Riches, the driver of the 997 GT3 Cup car in the video, has shipped his car all the way from Florida in order to compete in this week long event. He's competing for stage time. The biggest differences from a straight up performance rally are the facts that there is no recce (reconnaissance) for the co-driver beforehand and the Porsche cannot exceed 200kph (124 mph) without incurring a stiff penalty.
So in this case, Gavin's GT3 Cup is getting to 200kph quite quickly and driving into the corners blind (remember they couldn't do any reconnaissance ahead of the stage). Thus the co-driver's job (Gavin's wife Amy) is to navigate the car to the stage, and then during the stage, make sure the car doesn't exceed the speed limit of 200kph.
Gavin's run through the Crown Range is now the fastest recorded run of any car during competition.
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