Faster BMW i8 is coming

BMW is working on a more powerful version of its ground-breaking

There have been persistent reports that BMW is planning to deliver a thumping version of the i8 for its centenary celebrations next year, with some stories claiming it will deliver double the power of the current production version.

Sources at BMW insist that it would like to bring a faster version to market for the German car-maker's centenary -- something with a mid-three-second sprint to 100km/h.

The delivery method for the extra speed has been widely speculated over, with recent reports insisting it would swap its 170kW 1.5-litre three-cylinder petrol engine for an extreme version of the company's 2.0-litre inline four.

However, BMW’s board member for development Klaus Fröhlich has poured cold water on that, saying it simply isn’t possible to fit the larger four-cylinder engine inside the green supercar.

Speaking at the launch of the new 7 Series, Fröhlich said advancements in battery technology would be the most obvious way to extract more speed from the i8, rather than burning more fuel.

“It’s simple. The bore spacing on our V8s is 98mm and the bore spacing on the inline engines is 91mm.

“If we had a four-cylinder engine in the i8 we would have to add 91mm to the width of the car.

“Are we going to do that? It doesn’t seem very likely,” the engineer said.

“If we want to have more power in the i8 we have to do it with the e-motor, because the [battery] cell density we can use will get bigger and bigger."

The current road-going i8 has 266kW of power from its combination of a three-cylinder, turbocharged petrol engine sitting across the mid-sited engine bay and driving the rear wheels, with the front wheels driven by a 96kW electric motor.

It hauls to 100km/h in 4.4 seconds, looks like a supercar concept and drinks just 2.1L/100km on the NEDC fuel consumption cycle.

It draws its electrical power via either regeneration or plugging directly into a power socket, filling up a 7.1kWh lithium-ion battery that sits in the transmission tunnel.

And this is the bit that Fröhlich sees as the area with most performance potential.

“There is a clear trend line that sports cars in the future will be at least partially electrified and the technical systems to do it are already very clear," he said.

“Cell development in the batteries is very rapid. Energy density is what they talk about, but the Amperes flowing in and out is the key for performance and racing cars.”