We spoke to BMW ahead of the Frankfurt show, where the Munich-based manufacturer’s engineers will show off innovative updates to the 3-liter turbocharged six-cylinder in-line engine that won its category in this year’s International Engine of the Year awards.
The M4 GTS concept car features an innovative water injection system that brings an increase in power output and torque and a reduction in fuel consumption.
Why is BMW pursuing this innovation?
BMW thinks it’s on to a winner with the technology, cooling cylinders from the inside by injecting water directly into the combustion chambers and getting higher outputs from smaller engines through higher turbo boost levels.
According to BMW engineers, the new feature reduces internal engine temperatures from 400-500°C to around 330°C, with an improvement of 3-8% in fuel consumption. The water comes from a tank in the engine bay that drivers can fill up with distilled water, but the car will also use water from the air conditioning that would otherwise be dumped.
Is it just a BMW project?
BMW has called in some help for the initiative: German Tier 1 supplier Bosch has supplied its parts for the new system. It’s a demanding brief the new setup requires accurate metering and delivery of precise volumes of water into the cylinder as well as petrol.
What’s the long-term plan for the technology?
The German manufacturer might be showing off the water cooling system in a hot coupe, but it plans to introduce the new water cooling system in all of its turbocharged petrol engines, following up the production version of the M4 coupe with a three-cylinder engine in the 1-Series, which is currently undergoing final prototype testing. BMW says water injection will soon be as ubiquitous as variable valve timing.
What early test results is BMW getting from the 1-Series prototype?
The 1.5-liter three-cylinder engine benefits from three multi-point injectors that supply water directly into each combustion chamber, as well as indirectly into the inlet manifold. BMW tells us their testing has shown a power increase from 204ps to 218ps and a rise in torque peak from 280Nm to 320Nm.
August 19, 2015
