In keeping with the reputation that it has built over time, AC Schnitzers program for the new Z4 Roadster M40i covers a lot of ground. From form to function, we see the tuners imprint on the Z4 Roadster M40i, including the addition of several aerodynamic pieces to go with a new set of wheels, an equally new custom exhaust setup, suspension upgrades, and, of course, an engine modification program that adds more power to the Z4 M40is already potent 335-horsepower 2.0-liter turbocharged engine. All these upgrades are meant to improve the Z4 M40is overall appeal, and judging by this before-and-after video that AC Schnitzer provided, the upgrades are also significant in the way we see the German roadster.