Many of the products first tested in racing were later used in serial production. Here are just some of them:

1954:
Mechanical gasoline direct injection
(Mercedes Benz Silver Arrows)

1963:
Halogen lights
(Mercedes Benz at the Rallye Monte Carlo)

1965:
Non-contact ignition system (Porsche 906)

1971:
First ABS used in a race (Zeltweg, Austria – Dr. Marco in a Porsche 917)

2001:
Electronic gasoline direct injection
(Audi R8 at the Le Mans 24-Hour Race)

2006:
Diesel Common-Rail-System (Audi R10 TDI at the Le Mans 24-Hour Race)

Quote from the "Magazine on Bosch History", published 2002:

"... Proven in test running, or: Racing builds trust

Two main factors allowed Bosch to establish the system of high voltage magnetos: Then as now, Bosch maintained close contacts with important customers. If an idea convinced them, they could test it at an early development stage. If the customers were convinced that the product represented a valuable technological advance, it meant a big step forward in terms of sales: In this case it was the Daimler corporation that ordered the first magneto on September 24, 1902 for experimental purposes and later became one of the first customers to buy the serial product.

The second reason for the success of magnetos was their track-record in motor racing. Durability tests did not yet exist in the automobile press to prove or disprove product quality, so Bosch had to find eye-witnesses for the quality of its products. Around 100 years ago, they were the spectators and reporters at motor racing events. When cars with Bosch igniters won, the ignition simply had to be good..."