That maximises headroom for both the driver and passenger - allowing them to wear crash helmets - without affecting the butch silhouette. The exterior has a wealth of bulges and scoops, and is completed by the twin body stripes running from nose to tail.
As well as improving boot space, the roof means better cabin insulation and much improved aerodynamics - and the GTS could top 190mph as a result. The 8.3-litre engine is carried over unchanged, but the 500bhp and 712Nm of torque mean performance will be blistering, with the 0-60mph sprint taking less than four seconds.
All that power is channelled via a six-speed manual transmission to the rear wheels. There's no traction control or ESP stability control system, either, so the Dodge needs its wide rear tyres and limited slip differential to cope. Giant Brembo brakes front and rear will scrub off speed, while the enclosed roof will help body rigidity for better handling. The independent suspension is set up for maximum grip, with high-spec run-flat Michelin tyres fitted as standard.
The GTS is available in the US later this year, and while UK and European sales are as yet unconfirmed, it may be available in limited numbers. Dodge will give the car its first public appearance at next week's Detroit Motor Show.
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