Abstract
Franz (2005) pointed out that many average Americans modified the car as grass root inventor during 1915-1939. Kline and Pinch (1996) illustrated that American rural farmers modified model T as agricultural machine.
After World War 2, so called “Tuner” modified the car and they won the champion in the races. The tuned cars had often beaten other cars including the car that original makers modified. And then, some companies began to collaborate with tuners. They could survive in the automobile industry, although almost other companies could not.
As some researchers like von Hippel (1988, 2005) point out, these user innovations are critical in the industry.
Many researchers and critics insist that in the near future average consumer can design and make the product with new technologies as well as professional companies do. But the history of car modifications demonstrates that average consumer lost the power of modification except simple custom like wheel exchange.
