The new Mercedes-Benz SLK: Passion meets efficiency - Daimler

Two-stage chain drive for low noisePage 30The extreme compactness of the camshaft adjusters was achieved by the new,two-stage chain drive. This drives two secondary chains – one per cylinderbank – via a primary chain and an intermediate gear. All three chains can beindividually adjusted via a chain tensioner. This results in low tensioningforces and low chain dynamics, ensuring consistent timing and outstandingacoustic properties, with friction reduced even further. In short, the new chaindrive is compact and ensures low-noise operation.Exhaust system for stringent emission standardsThe exhaust systems for the SLK were developed to meet the exhaust emissionstandards Euro 5 and ULEV, as well as noise emission standards. The exhaustsystem for the 4-cylinder petrol engine consists of a firewall catalyticconverter, a centre muffler and two rear mufflers.The emission control system for the V6 petrol engine has a firewall catalyticconverter for the right and left cylinder banks. The exhaust gases then flowinto storage-type NOx catalytic converters. These are followed by a twin-pipecentre muffler and rear mufflers designed as reflection/absorption mufflers onthe left and right. The system is rounded off by two exhaust tailpipes on theright and left.ECO start/stop function with intelligent direct-startThe exemplary efficiency, with fuel consumption reduced by up to a quartercompared to the preceding model, is also due to the ECO start/stop systemwhich is fitted as part of the standard specification in all models – now alsowith the 7G-TRONIC PLUS automatic transmission.Realising an auto-stop and auto-start function at the high comfort level of aMercedes-Benz requires complex control logic, a number of new or modifiedcomponents and a heavy-duty starter motor. Operating principle:• As a general principle, the engine is switched off every time the vehiclecomes to a standstill (auto-stop function)• With an automatic transmission, there is always an automatic restartwhen one of the following conditions is met – the driver operates theDaimler Communications, 70546 Stuttgart/GermanyMercedes-Benz – A Daimler Brand