Stand by for the Boxster four
BY MARTON PETTENDY | 24th Mar 2012
The German sportscar maker’s first flat turbo-four is likely to power a new entry-level version of both the Boxster, which arrives in Australia in July, and the closely related second-generation Cayman coupe, which will make its global debut at the Los Angeles motor show in November before going on sale globally in 12 months.
Project leader of the MkIII Boxster, Helmut Widmaier, told GoAuto at the global Boxster launch that a downsized force-fed boxer engine was vital for Porsche to meet tightening CO2 emissions standards in both Europe and the US.
“Greenhouse gas legislation in the US and elsewhere is forcing us to reduce consumption,” he said through an interpreter.
“We think that we can achieve that and comply only with cylinder downsizing, and the four-cylinder turbo is really the way into the future.”Mr Widmaier said Porsche could easily justify a four-cylinder Boxster – but not a four-pot 911 – because its chief model rivals already came with turbo-four engines at base level.
He told us he believed Porsche customers were ready for a four-cylinder model.
“I can imagine it in the Boxster,” he said, “but not so much in the (911) Carrera – certainly not – because if you compare this to our competitors - the BMW Z4, Audi TT and Mercedes SLK – they have four-cylinder turbo engines already today.”Mr Widmaier said Porsche would only release a turbo-four boxer engine if it matched the performance of the new Boxster’s entry-level engine, which has itself been downsized from 2.9 to 2.7 litres and delivers 10Nm less torque at 280Nm – albeit over a wider engine speed range of 4500-6500rpm.
However, the new Boxster 2.7 - which nevertheless displaces more engine capacity than the original 2.5-litre Boxster first sold here in 1997 - produces 8kW more power (195kW) and accelerates the lighter Boxster to 100km/h one-tenth quicker than before in 5.5 seconds (in optional PDK auto guise with launch control) while consuming just 7.7L/100km and emitting only 180g/km, making it 15 per cent more efficient than its predecessor.
“The turbo allows us to reduce the number of cylinders, but still have similar performance compared to a six-cylinder engine, with reduced consumption.
“That’s what we are striving for - we want reduced consumption but we want to maintain power.
“The importance of consumption is increasing, but we have set the target that we don’t want to compromise performance.
“If we were to get a four-cylinder, we want to maintain the performance.”
“Downsizing will be the way of the future, but whether the four-cylinder turbo will replace the six-cylinder we do not know yet today,” he said.
“We welcome the four-cylinder, but the time we go into production is not decided.”Given Porsche has put on hold its plan to produce a new sub-Boxster entry-level model – based on the compact mid-engined BlueSport roadster concept from Volkswagen, which owns 49.9 per cent of Porsche – it is likely the company’s first turbo boxer-four will slot into the 981 Boxster line-up beneath the current 2.7-litre six as a new base model, potentially priced from under $100,000.
Mr Widmaier said Porsche is currently working to ensure the lower claimed fuel consumption figure of the downsized Boxster engine is close to the model’s real-world efficiency, which is not always the case with turbocharged four-cylinder engines.
“We are just at the beginning of our four-cylinder turbo development,” he said.
“One of our goals was not to have these disadvantages compared to the six-cylinder engine in real-world operations.
“Of course, the NEDC and US driving cycle tests are set up under clearly defined laboratory conditions. In the customers’ hands things are often different, but we have our own driving cycles to make sure that our set-up is customer-relevant.
“The regulations as stipulated by the NEDC are just an excerpt of the real world – they only represent part of real life.
“Of course, we don’t have the possibility to set up our cars specifically for Australia, but we have a special area around Stuttgart which we use for our set-up and there we try to make sure the next generation is better than the past.”Mr Widmaier said he was also confident the hallowed Zuffenhausen brand’s first turbo-four would not sacrifice the distinctive flat-six engine sound it is famous for in the quest for greater efficiency.
“One target in the development is not to change the character of the car.
“The charm of the turbo engine is that you have the maximum torque already at a low engine speed and the emotionality of the turbo is enhanced by that.
“What we have to do to maintain the emotionality of the turbo engine is to set up the emissions system in such a way that we get a more characteristic sound, so we do not really have any concerns that we would lose the characteristic sound.”While a downsized turbo-four roadster is locked in, Mr Widmaier ruled out a plug-in version of the new Boxster.
Porsche produced three battery-electric experimental versions of the previous Boxster, but says a production Boxster E will not be forthcoming until it can match the driving characteristics of its petrol-powered stablemates.
Mr Widmaier said an electric Boxster would be “very far” away.
“We are still in the middle of the research phase.
“For small city vehicles, electro-mobility is okay today, but to satisfy sportscar customers with electric drive, that’s currently not in reach yet – range and performance do not correspond with Porsche requirements.
“We produced the three Boxster E engineering cars to gather experience, but for the time being there is no market date timing to transfer this to the new Boxster.
“Until the typical Porsche driving experience can be delivered, there will be no Boxster E.”Mr Widmaier said battery-electric drive systems were a long way from matching the performance of petrol-powered Porsches, especially in the area of highway overtaking acceleration.
“I wouldn’t say that electric cars will never match sportscars.
“Although it’s charming to have maximum torque at zero engine speed, the mismatch between electric drive and sportscars – and the reason why we haven’t pushed this in sportscars - is that from, say, 120 or 140km/h, you lack the agility. This is the compromise of electric drive.
“Of course, we have to work towards that – we could always envisage transmissions that add agility at higher speeds - but this is a long way into the future.”Porsche already offers hybrid versions of both the Panamera sedan and Cayenne SUV, and its first plug-in hybrid model will be the 918 Spyder supercar, which is due to enter production in September 2013 – around the same time as its next additional model, the Macan compact SUV.
Senior Volkswagen executives recently also revealed Porsche would offer a plug-in version of the Panamera by 2014 – after which a Cayenne plug-in hybrid is likely to follow – but Mr Widmaier ruled out a plug-in hybrid version of Porsche’s smallest model.
“It’s very charming to use the boost of electric motors, but when you look at the additional effort we would have to invest in terms of cost, weight and space, you find that there are limits, especially when it comes to the space concept of the Boxster today.
“We are thinking about hybrid sportscars, but today we don’t see any possibility to achieve a worthwhile increase in power with hybrid models.”
