The Aston Martin DB4 was introduced in 1958, signaling a new era for the company. The DB4 was an entirely new car, using a new platform as well as a new engine. The new 3.7L dual-overhead camshaft straight six engine was designed by Tadek Marek and produced 240hp. During the course of production, five different series of the DB4 were made, including the Base Model, Vantage, and top of the line GT. The differences between each series are largely cosmetic, yet small changes such as ride height adjustments and interior updates are notable among the series. The GT model featured a more powerful engine and shortened wheebase, as well as more aerodynamic features. Nineteen of these GT cars were reworked and rebodied by Zagato to create the DB4 GT Zagato. In 2017, Aston created 25 slightly modernized versions of the DB4 GT that were known as the DB4 GT Continuation.