In accordance with one aspect of the present disclosure, an apparatus and a method of testing one of aerodynamic and acoustic characteristics of a vehicle is described. The method includes measuring a vehicle center using a gauge. The gauge includes a carrier section from which a pair of arms extend in opposed directions. Each of the arms has an axle center locator. The carrier section has a vehicle center marker. Upon determination of the vehicle center, the vehicle can be located in a wind tunnel at a predetermined location and exposed to an enhanced air flow.