Winged Warriors/National B-Body Owners Association
Winged Warriors/NBOA 3/8 Scale Wind Tunnel Model

Text by David Patik; photos by Sue George


[Tunnel Model] [Tunnel Model] [Tunnel Model]
This is the original 1968-1970 Charger 3/8 scale wind tunnel model, which was donated to the Winged Warriors/NBOA club in the early 1980's. This model was constructed by Chrysler NASCAR program engineers in 1967. It was originally built to test the wind characteristics of the new 1968 Charger. It was modified many times to test the aerodynamics of the 1969 Charger 500 forward grille area and fastback rear window; the 1969 Daytona nosecone (they tried several versions) and different wing ideas, and the 1970 Charger short track car. The wind tunnel model was tested at wind speeds of up to 250 mph.

Aerodynamics tests of bodies have been done since at least the days of the Chrysler Airflow. Chrysler built similar models of the 1966-67 Charger, Coronet and Belvedere, 1968-69 Coronet, RoadRunner, SuperBird and the 1971 RoadRunner and Charger. This is one of two musclecar era wind tunnel cars to survive. It is being restored to include all of the various front ends, wings and details.

Construction of this scale model car began by reducing to 3/8 scale the actual-sized paper drawings of the Charger body. From these shrinks, a hand-molded body was made, perhaps from modeling clay. From this was made a reverse mold, into which the fiberglass body was molded. This model weighs about 250 pounds.

[Tunnel Model] [Tunnel Model]

A cut-down heater core was used to simulate a cooling radiator. Behind this was mounted a variable speed electric motor, with an attached fan. Many tests were run to determine the best designed fan for oval track racing, but actually the different designs made little difference in car speed. The above photos are looking into the engine compartment where you can see the radiator area (where duct tape is applied) and the bracket that held the electric motor.

Aerodynamic engineer Gary Romberg used this model in 1969 and 1970 to test ideas for improving the Charger race body. If the wind tunnel tests were positive, full sized parts were handmade, then fitted to a rather crude test "mule" car. This was the odd-looking #71 car. It was known as the "mule of all mules". If these race parts worked well, they were produced by machine, then tested on the #88 car under the supervision of chief mechanic Larry Knowlton. Finally, the parts were distributed to Chrysler race teams.

The exhaust extensions were made to test the possible aerodynamic benefits of very long pipes. On the underside of the chassis there is a molded-in single exhaust system, including a muffler. Because of the detail on the K-member and rear springs, this chassis probably was used on many different wind tunnel bodies.

[Tunnel Model] [Tunnel Model] [Tunnel Model]
The wind tunnel model has three types of side windows: the original molded-in fiberglass, tin plates and wire screens. Vent-door-quarter windows were originally all molded into the body and aerodynamic tests were made. The side windows were later sawed out of the body, and tests were made with a combination of screened windows and plugged windows. The tin plates were likely used to support the modeling clay. Aerodynamic tests were done on side window possibilities because of various race track requirements and NASCAR rule changes.
[Tunnel Model] [Tunnel Model]

Look closely at the above photos showing the tubes around the window openings and in the roof area. The tiny tubes were cemented on at dozens of locations on the body. At each point is a hole in the body. Rubber lines connected each tube to a monitor, which measured the air pressure at each point (Velocity Points).

[Tunnel Model] The 1970 Charger front section was made slightly too large so modeling clay was used to make smooth body lines. This car's integral body ends between the wheels and grille, so different front end design sections could be fitted, including standard 1969 Charger, the Charger 500, long and short Daytona clay noses and the fiberglass versions. All will be made again as part of the restoration on this car.
[Tunnel Model] This is looking into the passenger's compartment towards the rear of the car.
[Tunnel Model] [Tunnel Model] This is just one of many wing heights and designs that were tested.


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