[Lee Stewart]

When Chrysler did their extensive wind tunnel testing on the 1969 Charger Daytona, they found that if they lowered the rear wing, the results improved. But as per NASCAR rules, you had to sell your car to the public and lowering the wing would cause the trunk lid to hit it. So the height was set to allow just enough clearance for the trunk lid to fully open. This was one of the areas that NASCAR took very seriously and to prevent any cheating, measured the height of the wing on each race car to make sure it was exactly the same as a production car.