BMW simplifies engine design

BMW'S future engine family will have a modular 500cc per cylinder design across the range to reduce complexity and production costs.

A gradual adoption of the 0.5-litre per-pot design will cover three-, four- and six-cylinder engines up to 3.0-litres to power most BMW vehicles.

While previous BMWs have used a wide range of engine sizes to differentiate performance levels, the German car-maker will extend its one-size-fits-all principle, with engine mapping and tuning – not litres – dictating power outputs,.

BMW could not confirm a date by which all vehicles would be using the new engine design, but said the transition had already started with the introduction of its first three-cylinder.

Speaking at the launch of BMW's first front-wheel-drive car and the third to use a 1.5-litre three-cylinder – the 2 Series Active Tourer – BMW Group Australia head of product and market planning Shawn Ticehurst told GoAuto the move to align engine design would result in more flexible manufacturing processes.

“To pick a random number – rather than develop four different engines that would cost an incredible amount of money, you can develop some similar components that will start to feed through,” he said.

“It means high-quality for all our engines and it means we can focus on some key components and integrate those in different engine sizes.

“It means we can move manufacturing around between different plants and that gives us a real flexibility to meet the needs of the market.” The plan is only chalked to cover up to and including 3.0-litre engines at this stage, but an extension of the principle could see the larger eight cylinder engines affected too.

“It is the start of what we call our new engine family and a focus around this 0.5-litre per cylinder principle,” Mr Ticehurst said “This engine family will grow throughout our range. It’s a new design language for engines that we are starting to talk about now and will flow through to a lot of our cars.

“We will start to see that engine range rolled-out gradually. It will start off with the 1.5-litre three-cylinder and then the 2.0-litre four-cylinder and then let's see where it goes.” The 1.5-litre engine already powers three different models under the BMW umbrella – the Mini Cooper and BMW 218i Active Tourer with 100kW and the hybrid BMW i8, in which a retuned version of the same engine pumps out 170kW.

The German car-maker has not specified which series will adopt the principle, but the cylinder capacity limitation would see an end to the 1.6-litre four-pot Mini and 1 Series engine.

If the regime were to extend beyond 3.0-litre engines, the 4.4-litre V8 that powers the company's 5, 6 and 7 Series as well as X5 and X6 SUVs could be under threat, but its 6.0-litre V12 as found in flagship 760Li would be safe.

BMW's range has been slowly transitioning to a rationalised engine range with the advent of reliable turbocharging and variable valve-timing allowing the easy alteration of power-output for different applications.

Today's F10 5 Series has just three different engine sizes, including the manic M5, but the E34 range of the 1990s was at one point offered globally with a four-cylinder, two different 'small sixes', two 'big sixes', two sizes of V8 and an M-Power straight six.

BMW says developing new engines under the principle would simply be a matter of adding or removing cylinders with some component sharing and a more unified design for all engine parts.

While the culling of engine variants may sound severe, Swedish car-maker Volvo has already announced an even more spartan range of engines with the company ultimately converting to a 2.0-litre four-cylinder for all its vehicles.