The first 6-cylinder Ferrari in history, with an engine designed by Aurelio Lampredi starting from the 4-cylinder of the 500 Mondial, the 118 / 121LM had a chassis similar to that of the 750 Monza but elongated. The 118LM had a 3747cc (280hp) displacement while the 121LM had a 4412cc (330hp) engine. During the 1955 season, the 118 / 121LMs failed to achieve significant sporting results, mainly due to the overwhelming dominance of the Mercedes 300 SLRs. Just four units were built.