The first Cadillac, now called the 'Model A', was mostly the Ford Model A which Henry Ford left in the factory when he pulled out his investors. Henry M. Leland took on the design, but with his own single cylinder engine. The 1904 Model B was an evolution of the Model A (which remained in production) but the engine was more powerful. Cadillac's first four-cylinder model, the Model D, was launched in 1905, but single cylinder Model C, E, F, K and M were produced up to 1906, with 4-cylinder Model G, H and Model L also being sold. A new Model S was sold in 1907 and 1908 and was still single cylinder, even though Cadillac customers now preferred the fours. In 1909 all this was swept away by the concentration on a single model, the four cylinder Model 30 with 3,707cc (226) 30bhp L-head. The Model 30 took Cadillac up to 1915 when it introduced the V8 powered Model 51.