Next summer, BMW will launch the M340i xDrive, an M Performance Vehicle that will sit below the forthcoming BMW M3 in the line-up - and the only regular 3 Series to use a six-cylinder petrol engine. To give us a taste of what to expect, BMW let us loose in its engineering prototype for a few fast laps of the Portimao race track in Portugal.
In the metal
Though the test car you see pictured here is wearing heavy disguise, BMW has already released preliminary images of the finished M340i (see it here in our news story), so we know it will build on the M Sport look with plenty of bespoke parts, unique alloy wheels (18s as standard, 19s as an upgrade) and lots of 'Cerium Grey' accenting. There's a subtle boot spoiler and large exhaust outlets poking out of an enhanced rear bumper, too.
Inside, the M Sport finish is again used as the basis for the car, with a few unique items such as chunky sports seats with seatbelts using the M Sport colours.
Given what BMW's M division did with xDrive four-wheel drive for the current M5, we shouldn't be surprised that it makes the M340i a lot of fun on track. While it doesn't have the same level of customisation as you'll find in the M5 (i.e. there is no rear-wheel-drive-only setting), in the Sport Plus mode, the M340i clearly sends most of its power to the rear wheels until there's a good deal of slip going on. Browse through our gallery and you should see how sideways you can get it, even in the middle setting of the stability control system. That's thanks in part to the standard M Sport differential (an electronically controlled item), which is tweaked for agility in the Sport driving modes.
But we realise that few will attempt to drift their M340i around and during this 'research' we also discovered how biddable a chassis there is under this car. It's a cinch to set it up for a corner and use the inherent balance to power through at high speed. What's more, it's really adjustable on the limit, with plenty of messages through the steering and seat about the levels of grip available.
With a fast-driven M2 Competition ahead, there was effectively no limit to how hard we could push the car, and it proved to be well up to the job. The brakes and tyres eventually needed cooling down, but the car never felt ragged, despite the elevated pace. And yes, the six-cylinder engine is sublime.
This all bodes very well indeed for the finished product.
The six-cylinder petrol BMW 3 Series has, for a few generations, been wonderfully fast and cultured, but nowhere near as focused on driving as the mighty M3 above it. That all changes with the 2019 M340i xDrive. It's a very different beast to a full-on M car, but our first taste in prototype form suggests that it'll appeal to just as many enthusiasts when it launches later in 2019. We can't wait to try the finished product.