New Mercedes C-Class Coupe not so rational

Sporting dynamics and style are the priorities over rationality and functionality for the new-generation Mercedes-Benz C-Class Coupe models that arrive in Australia from March.

Benz has adopted a philosophy that puts dynamics ahead of comfort and — perhaps bravely — style ahead of functionality to the extent that rear knee room has been cut by 25mm and boot space by 50 litres to 400 litres, despite the body being nearly 100mm longer overall.

“We made a statement to have this car. It is a more sporty car that compromises on rationality,” C-Class development director Christian Fruh told motoring.com.au at the international media launch in Spain last week.

Led by the new king of the entire C-Class range, the Mercedes-AMG C 63 S Coupe, which we have covered in a separate news story, the W205 two-doors are a fundamental overhaul of what has come before.

“We had to compromise to give this car the sexy shape. We really discussed that a lot,” admitted Fruh when quizzed about the car’s compact interior

“We thought it is more important to give the car a really good look and to sharpen its position because the back seat is not really the focus of people who buy the car.”

Those style statements include a longer hood, tapering glasshouse and roof-line that drops sharply from its highest point.

But there are also practical reasons for the squeeze; the need to fit bulkier powertrains including the C 63’s V8, a new exhaust system, lowering the front seats 40mm and even package protection for hybrids, although none are planned for the coupe.

Overall, the new coupe measures 95mm longer than its predecessor at 4686mm (the same as the sedan), 40mm wider at 1810mm and is 1mm lower at its highest point at 1405mm. The wheelbase is 80mm longer.

And it's not all bad news in the two individual back seats, because the cabin is wider and there is more headroom than the old car. The shape also delivers a slick 0.26 Cd aerodynamic coefficient.

Fruh said the other fundamental decision in separating the coupe from the sedan was to favour sharper handling over ride comfort.

The coupe shares the new ‘MRA’ longitudinal front-engine and rear/all-wheel drive architecture, 2840mm wheelbase and four-link front, five-link rear suspension layout with the C-Class sedan.

But it has been lowered 15mm in all possible suspension variations – the standard steel and class-exclusive optional Airmatic adjustable air springs, plus the steel sport option have all been tuned for sportier behaviour with damper and stabiliser settings up to 15 per cent stiffer.

“We wanted to make it more sporty and give it a better handling feel than the sedan and then we compromise a little on comfort,” revealed Fruh.

“We think people who drive this car, they love the feeling of a sportive car that feels very direct in steering, they want to feel the road … and actually to integrate that feeling better.”

The slick body also contributes to the handling prowess of the car because it develops little lift at speed and, Fruh says, is balanced equally front and rear. He points to tweaks such as the lip spoiler on the boot and rear diffuser.

“The lift coefficient in the back is 0.1 or 0.09, and at the front 0.7 or 0.8, so that gives the car even in the high speed good handling and not too much lift,” he explained.

“It’s a good figure for passenger car. It’s important not to have a big difference between front and rear so the car starts to stall.”

One area where the coupe can’t match the C-Class sedan is weight saving. While the new four-door saves up to 100kg over its predecessor, the coupe ekes out no more than 20kg.

But Fruh does claim significant torsional stiffness improvements, suggesting the coupe has been developed in a job-lot with the new cabriolet that comes in 2016 and shares some of its body reinforcements.

Not that Fruh was biting on that one: “What cabrio?” he deadpanned.