Sweet looking Coat hanger for the Boxster

Ya, they are made to give better contact at high speeds on the rear, but they are most effective with a front spoiler to keep the entire car either neutral weight or heavier (relative weight, lbs of downforce) at high speeds. Thats why you see all those front lip spoilers for sale too. F1 cars do about 3 g's around turns due to the combination of spoilers, body design, and tires. It simulates the car weighing like 4 thousand pounds at speed when in reality it doesnt (less inertia, but more "mass"), thus it can go around a turn faster. Fc=(mv^2)/(r). The more mass, the faster you can go around a turn. Which is why you could probably go around a corner in an F1 car at 20 mph and live, and at 200 mph and live, but if you only go 70 you might not have enough downforce to keep you on the road. Its crazy stuff like that that makes you tune specifacally to your car or the track.