German tuner AC Schnitzer has tuned the BMW Z4 Roadster, creating the ACS4 Turbo.
The modifications are designed for the range-topping sDrive35i. ECU changes mean the twin-turbocharged, 3.0-litre engine goes up from 302bhp to 355bhp.
The result is in an increased top speed of 178mph and a reduced 0-62mph dash of 4.9 seconds, a fifth of a second faster than the standard Z4. AC Schnitzer has also included a new set of springs and a sports exhaust system in the upgrade, to provide a more sporty ride and handling package
The ACS4 also has a new aerodynamic package, which includes a front spoiler, new side air vents for improved brake cooling, a two-piece rear spoiler and a chrome front grille.
It also sits on a set of 18-inch alloys, although the options list includes 19- and 20-inch wheels.
The interior has also undergone some minor changes – the Aachen-based tuner has put an aluminium cover on the iDrive controller, pedals and gearstick.