Here’s Porsche’s new 911 Turbo testing in sub-zero temperatures inside the Arctic Circle; both the Turbo coupé and the Turbo cabriolet are undergoing the last stages of their development ahead of their launch at the Frankfurt show in September.

The Turbo will be lighter than the previous model, thanks to the extensive use of aluminium in the body shell and most of the panels – with a saving of around 45kg, the new Turbo Coupé should weigh in at around 1550kg.

A reworked version of the last model’s 3.8-litre flat six increases power from 493bhp to 525bhp, and torque will rise from 479lb ft to just under 500lb ft. It uses three turbos to help deliver these increases while improving fuel consumption and cutting CO2 output. One of three is a smaller unit, which works from lower down the rev range to provide boost at low speeds, while the second and third cut in at higher speeds.

Two gearboxes will be offered – a seven-speed manual and a seven-speed dual-clutch PDK. As with the previous car, a PDK-equipped 911 will be faster than a manual car and more efficient, with lower CO2 emissions. With the increase in power, expect the new Turbo to hit 62mph in around 3.4 seconds.

Both cars will retain the Turbo’s trademark split rear wing, with its characteristic air intakes. The test cars' intakes are disguised with a surround from the last car – expect a new design for the production vehicles.