BMW touts technology to make engines more efficient
By GREG KABLE
| Published 05/18/06, 5:38 pm et
Hybrids are the buzz at the moment, but BMW engineers believe technology can wring more efficiency from the conventional gasoline engine.
An inline six with BMW's High Precision Injection system.
Testament to this is a broad-based engineering program recently initiated by the German carmaker that goes under the title of Efficient Dynamics. Rather than relying on one particular technological breakthrough to help achieve its goal of making upcoming models cleaner and more fuel-efficient, BMW says the path to the future lies in a series of advancements.
While BMW is committed to launching hybrid models in the years to come, most of the company’s research and development is focused on other technologies.
The biggest gain in efficiency will come from BMW’s High Precision Injection system, which makes its North American debut later this year in the German carmaker’s new twin-turbocharged, 3.0-liter inline six-cylinder 335i coupe. HPI uses a piezo injector similar to that used in BMW’s diesel engines. The injector is mounted between the valves and delivers fuel close to the spark plug, allowing more accurate metering of fuel and more efficient, higher-compression combustion. This allows the new BMW powerplant to operate in a lean burn state over a much wider range of driving situations than with the older sequential fuel-injection system, maximizing economy and leading to cleaner emissions.
Other technologies under investigation are known quantities: Lightweight plastic body panels, magnesium engine components and adaptive automatic gearboxes are already in production and used throughout the BMW lineup. Expect to see them further refined in years to come. Other technologies such as BMW’s Intelligent Alternator Control and Intelligent Energy Management await approval. The former uses an alternator that automatically decouples when it is not required. The latter uses an electrical coolant pump that only cuts in when it is absolutely needed. Together the two technologies promise 3 to 15 percent fuel savings, depending on the terrain and type of technology involved.
Other engine developments include new double Vanos infinitely variable valve timing, the adoption of larger intake valves, a nitrogen dioxide filter and, as with today’s 3.0-liter inline-six, a lightweight magnesium block.