Volvo Penta D13 IMO III is an in-line 6-cylinder, 12.8-liter, diesel engine using a high-pressure unit injector system, overhead camshaft, and a twin-entry turbo using a water-cooled exhaust manifold. This contributes to world-class fuel efficiency and excellent operating economy, combined with very low emissions. It´s designed to cope with high back pressure and high-sulfur fuel – up to 1,000 ppm. The SCR (Selective Catalytic Reduction) exhaust after treatment system is tailored for a perfect fit. The SCR unit, also a silencer, reduces noise by 35-40 dBA. Volvo Penta has been able to fulfil IMOIII exhaust emission targets while maintaining the same low fuel consumption. And thanks to SCR, the engine power output remains unaffected.