Vintage Tether Model Racing Cars are the precursors to the Radio Controlled Racing Car of today. They are model racers ranging from approximately 8 - 22 inches long, 3 - 4 inches wide and are powered by model gasoline (nitro fueled) engines. Made from wood and metal, and later all metal, or metal and fiberglass, and fitted with rubber tires with metal rims,  the cars were designed to be tethered to a circular racing track center post. They would be run around these tracks at great speeds - sometimes exceeding 100 miles per hour. Variants of these cars were designed to run around raised tracks using a rail tether system ("railton").  Tether Cars were first built in the late 1920s . By the late 1930s, there were many tracks and  racing clubs. After the end of WW2, returning soldiers eagerly took up the hobby and the late 1940s were perhaps the high point of these racing cars. The very earliest cars were home made by hobbyists familiar with machine tools. They represent a kind of folk art and the early ones with beautiful designs and fast engines and in original condition are highly sought after today. They are often known in the USA as 'Indy Cars' because they resemble the beautiful shapes of early American racing cars as run at the Indianapolis Raceway and other race tracks throughout the USA. Tether model racing cars can often be found on eBay (do a search for 'tether' within the Toys and Hobbies category), and if original, can be worth many thousands of dollars.  Early magazines such as The Model Craftsman Magazine, had numerous articles and build-it yourself plans relating to tether racing cars. (Issues from 1930s-1950s). These magazines can often be found on eBay and are a good way to read about these early racing cars.  Some 1930s-1950s magazine articles presented plans to enable readers to construct their own gas powered model racing cars and these articles (originals or reprints) are sometimes available on ebay - again - do a search for "tether" in the toys and hobbies category.                         By the 1930s,  small specialty commercial manufacturers began making tether racing cars for the hobby market. . Some of these company names are: Ohlsson & Rice, B B Korn, Champion, Hiller, Dooling Brothers and McCoy (Duro-Matic)  .These cars were powered by engines made by Dooling Brothers, Dennymite, Bunch, Ohlsson & Rice,  Hornet, McCoy (Duro-Matic), Herkimer (OK Cub),  Super Cyclone and many others.    The larger cars ( approximately 13-22 inches long) were powered by powerful spark ignition engines with .60 -.61 displacements . Smaller cars - approximately  9-12 inches long - ( also known by collectors as "Mite Cars" ) were powered by engines with .19-.36 displacements.   All these cars, if original , are highly collectible today and fine examples can be worth many thousands of dollars.  Even incomplete original cars and original parts for early cars are very desirable.   Today, craftsmen and hobbyists all over the world are building modern gas powered tether cars either as working replicas of the original vintage cars, or as new modern designs  for display or racing. In the 1950s and later, larger hobby manufacturers such as Cox made more modern versions of gas engine powered model racing cars, using plastics as the primary material . These are also highly collectible today and also can be found on eBay - do a search for 'Cox Racing Car'  or "Cox" in the Toys and Hobbies category.   One final word on valuations of the old vintage tether cars - they are not common - in fact some are truly rare - and are highly decorative collectibles - look great in the den or family room - and are probably undervalued at todays prices on eBay.    Keep an eye out for them at flea markets and antique fairs. Since their values are not well known, you may be able to grab a bargain!!