In early-1902, he established the Buick Manufacturing Company, with the objectives of marketing engines to other car companies, and manufacturing and selling its own cars. Manufacturing and development problems ensued, and, at the end of 1902, Buick was out of money with only one car to show for his work. The concentration on development had produced the revolutionary "Valve-in-Head" overhead valve engine. This method of engine construction produces a much more powerful engine than the rival side valve engine design used by all other manufacturers at the time. Overhead valve engines are used by most car manufacturers today, but now only GM and Chrysler produce the "push-rod" variant with any regularity. Since overhead cam engines are design variants of OHV engines, it is fair to classify virtually all modern engines as derivatives of Buick's invention.