DMSBD Tech Tips

History of Wheel, Lane, and Timer Swap
by Tex Finsterwald

Official Soap Box Derby wheels were available as early as 1936. It was not until 1954 that official SBD wheels became mandatory. In the thirties, an official wheel might be any wheel identified with the SBD logo. B.F. Goodrich and Hedstrom made wheels specifically for SBD use. In 1941, Firestone developed a SBD wheel. A wheel based on the Firestone design was manufactured for SBD use as late as 1975 and may still be used today. These steel wheels were made by both Firestone and Goodrich and assembled in several locations around the country.

The first plastic wheel was developed about 1978, but was found to be unsuitable for racing. The plastic Z-glass wheel used today debuted in 1982 and was manufactured in Mt. Clemens, Michigan. Manufacture of the Z-glass wheel was later moved to Akron. Wheels are the single most important factor in how quickly a gravity racer gets down the hill. In the days when people ran on their own wheels, we used to say that the car only served to hold the wheels up. As time went on, people felt that wheels should be taken out of the picture.

In 1958, the All American SBD was run on wheels issued to the champions in Akron as an attempt to take wheels out of the picture. The problem with issuing wheels was that variations in manufacture resulted in wheel differences that were greater than the differences in the racers. This is still true today. Also, the differences in the lanes became of greater importance in determining race winners. Even when one attempts to calibrate lanes, track variations due to temperature changes through the course of a race, change which lane is fastest at a given time. Realize, that the difference between the fastest and slowest cars of today is less than the blink of an eye. Swap racing resulted from the desire to eliminate the effects of wheels and lanes on the outcome of derby races.

Akron and others used conventional photography to determine heat winners going back to the thirties. Polaroid photos came later and of course digital imaging as the technology emerged. In the early days of photo swap we used Polaroid photos to compare margins. The Brower brothers, Ollie and the late George, of Ventura, CA originated PHOTO swap racing in 1976. In 1978, the Flint, MI SBD group under the directorship of Tex Finsterwald ran the first known swap race east of the Mississippi introducing this type of racing to the Midwest. In 1979, the NDR Championships in Chattanooga, TN were run with a photo swap format. In 1978, some folks on the west coast started experimenting with timers to measure the differentials between racers rather that using photos to measure the differentials. The 1981 NDR Championships in Allentown, PA were run using timer swap. Every NDR race since then has used timer swap and it has become the method of choice for gravity racing.

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