Ed Baynes readies a tether car for competition in the moment called "pushing off." The tether itself is faintly visible in the photo, attached to the frame of the car.

Courtesy of Sandia National Laboratories

Tether Car Races

We already know that the cars can achieve speeds faster than 200 miles per hour (321.9 kilometers per hour) and they pull with a force of up to 91 times their own weight, but how do these cars actually race on a track?

Each car has a metal bar attached to the body called the panhandle. The panhandle attaches the car to the steel cable and post in the center of the circular track. Official WMCR racetracks are made of flat concrete and are built in two different sizes. The first size is a 70-foot (21.3-meter) diameter track that provides the cars with six laps for a total distance run of one-fourth of a mile (.4 kilometers). However, the WMRC rulebook states that new tracks should be built at 19.9 meters (65 feet, 3 and 1/2 inches) in diameter and allow 8 laps of running time, equaling 500 meters (.3 miles) total.

Races are won by averaging the speed of eight laps compared to the averages of other drivers. The driver decides when his or her car is at its maximum speed, and then the laps are counted from that point forward. Drivers have three minutes to stop the race if they feel their car isn't performing correctly. Each driver is assisted by up to two helpers to start his or her vehicle. To start the car, the driver or a helper pushes it forward with a stick, turning on the fuel switch. Another helper, called the horser, holds the 33-foot (10.1-meter) long steel cable off of the ground until the car is going fast enough to hold the cable up by its own force, which usually occurs around 80 miles per hour (128.7 kilometers per hour) [source: Macropoulos]. To stop the tether car, a broom is used to knock the fuel switch down, shutting off the fuel to the engine.

In the United States, there are only three official tracks still in use. They're located in Whittier Narrows, Calif., Seaford, N.Y., and now there's a portable track located in northern California, too. Protective fences are built around each track due to the extreme top speeds and the tremendous force exerted on the car can cause parts of the vehicle to fly off or break during a race.

Although there are only a handful of tether car members and racetracks across the United States, those involved in the sport are committed to this 70-year-old hobby.

For more information about tether car racing and other related topics, follow the links on the next page.