- Published in Focus.
Europe is a hotbed of technological innovation, but when it comes to emissions levels in diesel powertrains, we haven’t kept pace with engineers in the US.
In part it’s due to the emissions regulations that European OEMs have to meet being less stringent than those in the US, but in 2014 Euro 6 will come into effect, forcing companies to reduce diesel emissions even further, particularly NOx levels. And this is where the work being done in the US could become invaluable.
Both GM and Ford produce diesel engines that, by European standards, are large. However, GM’s 6.6-litre V8 Duramax and Ford’s 6.7-litre V8 Powerstroke still manage to meet federal government and, perhaps more importantly, Californian government requirements.
Vehicles with a gross weight of between 3,885kg and 4,535kg are certified to California’s LEV II standard. NOx emissions are limited to 124mg/km, which is between the Euro 5 and Euro 6 passenger car standards.
Euro 5 specifies 180mg/km for passenger car NOx emissions, while Euro 6, when it comes into affect in 2014, will set the limit at 80mg/km. So it’s an impressive achievement that the OEMs’ engines produce so few NOx emissions, especially in heavy-duty pick-up trucks like the Ford F-250 and GM Sierra.
Not that meeting the targets has been easy. Both GM’s and Ford’s engineers thought that the regulatory requirements were going to be hard to meet.
“We were struggling to understand what technology would be needed to meet the required levels. There were a fair amount of people in the organisation that felt it was going to be difficult,” says Adam Gryglak, chief engineer of Ford’s Powerstroke engine.
So what areas of development can European engineers look to when they are seeking to meet emissions targets?
Ford’s diesel powertrain development is shared between the US and Europe. Gryglak says: “The fundamental design is global in nature. We go through content and get insight from both sides of the pond. A lot of the technology is common. The basic structure may be different because of the engine size but the fundamentals – the fuel system, turbocharger, exhaust gas recirculation and cooling – are similar. So we do have best practices based on experience.”