Volvo’s R&D boss Peter Mertens is confident that the company’s experimental 444bhp triple-charged four-cylinder engine has a future in high-performance production models.
Having unveiled the most powerful version yet of its new 2.0-litre, four-cylinder, Drive-E engine line-up in October, the Swedes have now installed the system in a Volvo S60 Drive-E for further assessment.
The technology – called Drive-E High Performance Concept by Volvo – combines two turbochargers with an electrical ‘e-booster’ to provide a strong power output throughout the rev range.
The ‘e-booster’ is used to spool up the turbochargers when the engine is running at low revs, dramatically reducing turbo lag and enhancing off-boost performance. As well as 444bhp, the engine possesses peak torque of 369lb ft. By comparison the most powerful standard variant in the Drive-E engine family currently produces 304bhp and 295lb ft.
Mertens said the engine could be a natural fit in Volvo’s Polestar performance models in years to come: “We haven’t yet decided whether we will bring it into production, but speaking as the boss of research and development my personal opinion is ‘of course we are’. It would be a pity if we did not. Assume that it was one of the next-generation of Polestar engines. Wouldn’t that be a nice solution?”
Should Volvo build a road-ready version of the Drive-E High Performance Concept, it could set new standards for specific output from a two-litre, four-cylinder mass production engine. The 355bhp unit in the Mercedes-Benz A45 AMG currently sets the pace, although that car is likely to be usurped when the Volkswagen Golf R400 reaches production with its anticipated 395bhp.
Volvo chiefs admit that it is partly the performance of such engines from its rivals that motivated them to embark on the High-Performance Concept.
“We saw that Mercedes had got 360ps,” said Michael Fleiss, boss of the powertrain department. “I thought, ‘wait a minute, we are the best at developing two-litre engines, so we have to do more’. Then VW and Audi showed that 395ps [in the Golf R400] and 420ps [in the Sport Quattro] is possible.
“So then we started to think about doing an engine with 450ps, just because we can do it. At Volvo we love a challenge.”
The unit is based around Volvo’s standard VEP engine architecture, but has a lower compression ratio, reinforced conrods and stiffer valve springs.
It also features additional measures to improve the cooling and lubrication systems and the new petrol unit is also supplemented by a fuel pump develop in conjunction with Denso that runs at an unusually high 250-bar pressure, up from the standard engine's 200 bar. The size of the fuel injectors has increased from 20cc to 25cc. “It’s a unique system but reliable,” says Fleiss.
Volvo engineers claim that this new forced-induction set-up “enables a very dynamic drivability without any turbo lag.” The company's suppliers AVL, Denso and Volvo Polestar Racing have all been involved in the system’s development, while the e-booster has been sourced from Valeo.
Mertens said: “When we launched the Drive-E powertrain family, our aim was to deliver the most advanced four-cylinder engines in the industry based on emissions and fuel consumption relative to performance and drivability. The 444bhp High Performance Drive-E Powertrain Concept demonstrates this ambition and the versatility of the Drive-E powertrains.
“It may sound odd, but this 444bhp powertrain concept is an important part of the Drive-E development program. Down-sizing must offer customers attractive and usable power for broad scale emissions reduction to work. Compact powertrains also free up space and weight in the structure of the car, which can be used for electrification and even further emissions reduction. And that is our ultimate ambition."