New three and four cylinder engines coming soon
BMW Group has just revealed details on its annual Innovation Days the updated version of their EfficientDynamics engines.
At the moment, BMW uses the “B” family of engines that were introduced early in the decade. Its B38 and B48 petrol units, and B37 and B47 diesels will soon be replaced by 3- and 4-cylinder mills increasing its performance and reducing fuel consumption. Highlights for the gas engines include turbocharging, direct injection, variable intake valve lift (Valvetronic) and continuously variable intake and exhaust valve timing (Double VANOS). Exhaust manifolds also differ between the three and four cylinder models with aluminum for inline three engines and steel for inline fours.
BMW adds that the direct injection system and fuel pump have been revamped to enable a more precise fuel metering and improved emissions quality over wide load ranges. For better thermal efficiency, its cooling pump has now a separate outlet for coolant to the cylinder head and engine block.
The automaker claims that refinement has been improved with the use of single-piece timing chain that along with a new belt drive uses an L-shaped belt arrangement. These improvements are said to have made the new engines run more silent.
Diesel engines get a new “form honing” system that reduces friction losses at from idle while reducing engine noise higher up the rev band. With these upgrades, there will be a bump in output and up to 5% reduction in fuel consumption and emissions. A new addition to the BMW diesels is multi-stage turbocharging (with twin turbos) which was reserved for the more powerful six cylinder turbodiesel engines. Another new Selective Catalytic Reduction (SCR) exhaust after treatment system using AdBlue urea injection on all 3- and 4-cylinder diesel engines.