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Mercedes-Benz's AMG performance division is set to kick off its 50th anniversary celebrations at the Geneva motor show in early March with the unveiling of a uniquely styled four-door concept - the GT 4 as it is known internally.
Set to provide clear hints to the appearance of an upcoming production version of the new four seater, the new Mercedes-AMG super sedan is set to replace the CLS Shooting Brake when it reaches Australian showrooms in 2018, featuring a 450kW plus twin-turbocharged 4.0-litre V8 engine and practical liftback style rear tailgate similar in style to that used by the Porsche Panamera.
The GT 4 will become AMG's third dedicated series production model line, following on from the SLS and the existing GT.
The arrival of the GT4 in concept form will complement the planned unveiling later in 2017 of AMG's recently announced limited-volume, F1-inspired hypercar in what is set to become a pivotal year for the brand.
Targeted at the the Porsche Panamera, BMW 6-series GranCoupe and Audi A7/RS7, the new Mercedes-AMG model, codenamed X290, is the brainchild of AMG boss Tobias Moers.
Original plans for a model in the mould of the GT 4 were first aired in a series of patent applications filed by AMG in 2012. At the time, plans centred around a long-wheelbase version of the SLS featuring two gullwing doors and a pair of small, rear-hinged rear doors.
More recent plans for the performance four-door model subsequently became more closely linked to the current GT. But while the latest addition to AMG's line-up will share key styling cues and elements of its mechanical package with the company's headlining two-door, sources say it will be based on a different platform from the bespoke aluminium structure used by AMG's more sporting Porsche 911 rival.
The basis for the GT 4 is parent company Mercedes-Benz's modular rear architecture (MRA), as used beneath the C63, E63, and S63. It has been specially modified for the GT 4, with what insiders at AMG's Affalterbach headquarters describe as "unique" wheelbase and track width measurements.
Other dedicated features include the added use of lightweight materials within the floorpan and body structure, most notably aluminium and hot-formed high-strength steel, the adoption of which is aimed at lowering the weight of the new model to below that of Mercedes-AMG's existing MRA-based models in the search of greater performance potential and enhanced handling characteristics.
Power for the GT 4 will come from the latest evolution of AMG's twin-turbocharged 4.0-litre V8, already confirmed for the new E 63. Among its developments is the adoption of new twin-scroll turbochargers mounted between the cylinder banks. The new turbos are claimed to provide improved induction qualities over the more conventional units used in the existing version of the M177-designated engine.
The engine is tipped to be offered in two states of tune from the start of sales, with both standard 4Matic+ and S 4Matic+ models. In initial range-topping S 4Matic+ guise, the GT 4's engine output is expected to top the 450kW of the new E 63 S 4Matic+.
It is understood that Mercedes' performance car division is considering coupling the engine with a newly developed integrated starter generator (ISG). The move would not only provide it with the ability to deliver short periods of added performance via a 15kW electric motor mounted within the gearbox but also offer instantaneous start-up, with what one engineer with knowledge of the new system referred to as "seamless" stop-start qualities.
The ISG operates via a 48V electrical system, suggesting the GT 4 could adopt a moderate-sized lithium ion battery as part of its arsenal of high-tech developments.
The engine will also feature dynamic mounts designed to suppress load changes during hard cornering and be combined with the a new nine-speed version of AMG's Speedshift MCT automatic gearbox.
The transmission will be coupled to Mercedes-AMG's 4Matic four-wheel drive system, which features a fully variable apportioning of power between the front and rear wheels. It will also incorporate a 'drift' feature that allows the driver to channel power exclusively to the rear wheels in a move aimed at promoting oversteer.
Also likely is a less powerful six-cylinder variant of the new AMG model using Mercedes-Benz's new turbocharged 3.0-litre in-line engine, likely in combination with an ISG to develop in the region of 300kW.
The GT 4 will be underpinned by a largely bespoke suspension system that is being developed to provide unique dynamic characteristics, with greater camber adjustment and wheel control than those delivered by the suspension used on other MRA-derived AMG models, along with revised steering rates. It is not yet clear whether the GT 4 will include the three-chamber Air Body Control air springs used by the latest E 63.
AMG is on a roll at the moment, with booming global sales. Moers, who was made chairman in 2013, said the performance division is approaching the size that Stuttgart neighbour Porsche was in 2010 before the Macan SUV was launched.
In recent years AMG sales have boomed, with sources suggesting that the recent addition of models such as the turbo 3.0-litre V6-powered C43, E43 and GLC43 will help to push AMG volumes to well over 80,000 units this year.
The AMG line-up currently supports 31 models, with a plan to expand to 48 models in the future.
2 Comments
German sites indicate this is a 2019 model and will be based on the new CLS platform. Given there are no spy photos of this car on the internet it would seem unlikely to be ready next year. Regardless it should be better looking than the Porsche.
Hopefully can slash the weight to be much lighter than the fat pig Panamera. Originally said to be lighter than the hideous first gen model it turned out to be heavier.