German tuner Techart has revealed the GT Street R Touring – a jaw-dropping sports car based on the Porsche 911 Turbo S, touting a raft of aerodynamic tweaks, lightweight materials and up to 789bhp.

It's said to have been built solely for "performance enthusiasts", combining "everyday practicality with uncompromised driving performance".

Over the standard 911, the GT Street R Touring gets an aero-optimised bodykit with 40 individual components, including front and rear bumpers and flared wheel arches together with a bonnet, front wings, side skirts and larger air intakes made of carbonfibre. 

Its new rear-mounted, "racing-inspired" ducktail spoiler is also carbonfibre, making it 60% lighter than the one fitted to the standard Porsche while enhancing engine cooling, according to Techart.

The twin-turbocharged 3.7-litre flat-six engine gets reworked internals to produce 700bhp and 663lb ft of torque, but it can also be ordered with the most powerful upgrade Techart has yet offered, sending 789bhp and 701lb ft to all four wheels for a 0-62mph time of 2.5sec and a maximum speed of 217mph.

This means it's as quick to 62mph as a Bugatti Veyron, and its 217mph top speed matches that of the new V12 hybrid Lamborghini Revuelto.

The extra power originates from an ECU remap, turbochargers with improved airflow and reconfigured gearbox ratios over the standard 700bhp tuner car.

The car gets an in-house developed sports exhaust system, complete with wider twin exits and its own set of valves to make it quiet when cruising and louder on track.

To improve handling dynamics, the GT Street R Touring also has a 30mm wider front track, springs lowered by 25mm, adjustable coilovers and forged lightweight alloys of 20in or 21in diameter.

It can also raise its nose for speed bumps or level crossings - a feature carried over from the standard factory car.

Changes to the interior are subtler, extending from the bespoke Techart steering wheel and trim pieces finished in carbonfibre or aluminium to the standard sports seats reupholstered in leather and Alcantara.

An 'exclusive package' is available to add decorative stitching, embossed details on the headrests and armrest and extended leather.

Techart said it will sell 25 examples of the GT Street R worldwide, with the conversion available from €98,250 (£83,732) over the price of the standard 911 Turbo S, itself costing £180,600. Deliveries are set to begin in May.