Time to stop counting cylinders

Volvo senior vice-president for research and development, Peter Martens.

While others push their electric offerings and super-long-range plug-in hybrids, Volvo's main punch at the Frankfurt Motor Show is to do with its plans to make its engines with four cylinders only - or less.

The Chinese-owned Swedish concern has its own electric and hybrid offerings, but its senior vice-president for research and development, Peter Martens, says that Volvo's more conventional petrol-powered and diesel- powered future cars will have smaller displacement and fewer cylinders than its current four, five, six and eight cylinder range of vehicles.

"It's time to stop counting cylinders", Martens says. "The [Volvo] concept at Frankfurt proves that downsized engines can go hand-in-hand with our customers expectations on luxury and driving pleasure."

His company's new so-called modular "Volvo environmental architecture" (VEA) four-cylinder engine range will feature direct injection for its petrol engines and common rail for its diesel units, and Martens says, the new engines are also ideal for hybrid applications and will reduce fuel consumption and CO2 emissions without sacrificing performance.

"We will develop four-cylinder engines with higher performance than today's six-cylinder units and lower fuel consumption than the current four-cylinder generation."

Volvo says its VEA range, designed solely for transverse application, will reduce the number of unique engine parts by an impressive 60 per cent, and could be about 90kg lighter than the current range and improve fuel consumption by up to 35 per cent. There is a remarkable similarity in Volvo's approach to its conventional power units with that of Mazda with its holistic Skyactiv approach, where weight savings and efficiency improvements conspire to produce lower emissions and fuel use without compromising performance.

Unlike Mazda, it is expected that Volvo will reinforce the performance of its four-cylinder petrol units by having turbochargers of varying capacity, designed to fit into the aspirations of the various demographics of its potential customers.

Volvo is also evaluating its recently announced kinetic energy recovering system, which captures braking energy that would otherwise be dissipated as heat in the form of a 60,000rpm flywheel. The tractive force on tap from the device means that less fuel-efficient activities like accelerating from rest and overtaking will sap less energy from the power unit by allowing access to an extra 50kw without requiring heavy throttle use. KERS, which has already been used in Formula 1, is expected to realise savings of up to 25 per cent even with current power units.

Another similarity with Mazda's Skyactiv set-up is Volvo's modular structure system, known as scalable platform architecture, which will mean that its frames and platforms will be from 100kg to 150kg lighter than those currently in use.

Volvo says its SPA setup should allow it to build its future models from the same modules because they would be adjustable for wheelbase length and track width allowing significant cuts in development, tooling and manufacturing costs. Combined with the new series of engines, Martens says: "Along with the new engine range [SPA] will enable us to be on par or even beat our toughest competitors in driving dynamics and economy."