Debuting at the show’s press day on 29th September, the Mercedes-AMG GT Roadster will be offered in two forms, with the more powerful GT C version capable of 196mph.
Like the GT Coupe on which the car is based both versions will use a 4.0-litre twin-turbo V8 petrol engine, driving the rear wheels through an AMG seven-speed dual-clutch auto transmission. In 436hp form the V8 produces 630Nm of torque, which gives the car a 4.0-second 0-62mph time and a top speed of 188mph. Combined cycle fuel economy is 30mpg with CO2 emissions of 219g/km.
The more powerful GT C offers 557hp and 680Nm, which cuts the 0-62mph time to 3.7 seconds, as well as adding 8mph to the terminal speed. The fuel economy is 24.8mpg, alongside 259g/km of CO2 emissions.
The power upgrade brings the GT C within 28hp of the range-topping GT R, and the newcomer also gains several styling and technical cues from the GT R. Notable among these are active rear-axle steering, an electronic locking differential on the axle and AMG Ride Control sports suspension. The rear wings are enlarged, which opens up more space for the rear wheels to be an inch wider and 20 inches in diameter instead of the 19-inch versions of the GT version. Also the front brakes are 30mm larger in diameter.
Both cars use a fabric hood, which opens and closes electrically within 11 seconds at speeds up to 30mph. The soft top, which is three-layer fabric with a low-weight magnesium/steel/aluminium frame, can be specified in either black, red or beige to suit the 11 exterior and 10 interior colours.
Order books for the two new roadsters are expected to open towards the end of 2016, at prices yet to be announced. Industry sources say they will be £10,000 more than their coupe sisters, which would price them at around £107,000 and £120,000 respectively.