W What is the recipe for a two-door 3-series coupé? It is clear: two doors away, bigger ones in, roof flatter, suspension harder, steering heavier and only the big engines in the bow. Uh - no. If it were that easy, everyone could do it, what should the BMW engineers do all day? So back to the beginning: The two-door 3 Series (which they made the 4 Series for the predecessor in line with marketing requirements) should be something special. Dynamic, sure. But also comfortable. Sounds like a dilemma. But isn't it, as BMW shows in a workshop long before the presentation of the four-car in early summer and its market launch in late autumn.
Show? Yes, but above all driving. The two test cars are camouflaged over a large area, but the right cars are already hidden under the black and white film, in our case an M440i xDrive with adaptive chassis and a 430i with optional sports chassis, conventionally dampened, both with electronically controlled limited-slip differentials.
With regard to camouflage, bad people could well get the idea of asking BMW why they are not basically offering the new 4 Series that way. Then the topic with the - well, let's say - prominent kidney would be elegantly settled. Appease benign people: It's nice that there are different tastes. And it's even better that we can't go into that any further today. See camouflage. What would Goethe say? 'Strong beer, acrid tobacco and a maid in plaster, that's my taste.' Quote curtain closed.
Lower, wider! Harder? No
Open the 4-person door: get in. Flatter roof, frameless panes, otherwise 3. Which is no harm. Stop, driver and Co. have to fish their seatbelts from the B-pillar. The ergonomically fitting seating position, as usual, has a compensatory effect, which is sharpened a bit in the 4-seater due to the lower hip point. When the roof comes down 57 millimeters, the passengers also have to be closer to the asphalt. It is conducive to contact with this and the deep focus that promotes dynamism in general. Compared to the 3 series, it drops by 21 millimeters - even without occupants.
Well, we already got that when we pulled out of a parking space , felt at the latest when entering the first roundabout. Hoax. With a serious background. Because although it is currently difficult to sell cosmetic interventions as a new model for cost reasons, BMW went really deep into the current 3 Series. From the stiff (and therefore more expensive) body structure to wheel suspensions to spring elements, steering and final coordination, all the signs stood up: You should be a sharp 3 Series again - just like before.
Mission accomplished, but as you please the 4-series one on top without destroying the comfort zone of its comfort-conscious occupants? We find out about this during the turn on secondary routes in the hinterland, an area with little traffic and many curves. Our guide: Jürgen Metz, BMW chassis professional and Eifelaner (or the other way around?). He is not only familiar with the area, but also with thrust fields, damper detections and spring rates, pulls us across the country at the right speed.
Home, your curves
Hach, this row six Turbo of the M440i actually belongs on a pedestal, no matter how much power it actually throws out. Alone how it sounds fine, pushes juicy and turns cultivated. Bavarian motor works. In this case with 374 HP and 500 Newton meters plus up to 11 HP electrical boost via 48-volt mild hybrid with starter generator and extra battery with 11 Ah. The system, which recuperates up to 12 kW and enables rolling up to 160 km /h without a motor, is already available in the 5 Series, but the 4 Series has it before the 3 Series. Either way, the M440i takes great pleasure in snacking on curves at home. Dahoam, as they like to say at BMW. Jürgen speaks German. That's good.
Also good: how the 4 Series drives. The package of measures against the 3 Series is effective. With a word like that, you usually switch off quickly, but here the dynamics respond: 23 millimeters wider rear axle track, modified camber values, struts in the area of the rear axle and in the front end between the strut domes and the body. The steering precision benefits at the front, the stability at the rear when accelerating sideways. Jürgen reveals that the developers build on the experience with the basic model for every derivative and therefore work more specifically.
Previously, driving dynamics boss Jos van As emphasized that steering and suspension are much more important with a stiffer bodycan be more precise. 'You don't have to take into account twists that tend to cause delays and overshoots.' The result is a precise part like the four-wheel steering with fixed manual torque without artificial weight - even in dynamic mode.
No wonder, simply buying a steering from the supplier and planting it does not come in question. The part must be physically fitted, free of tension and protected against vibration. As seductive as electric steering systems may be, you have to get a grip on their friction and apply them to the car, explain the BMW guys. That is why the steering usually comes at the end, after all, the gear ratio and manual torque have a direct effect on handling, comfort, driving safety and character. With the 4 series, the latter is easy to grip, round, precise. No 'by the way' steering, but one that connects the driver directly without stressing him out, because the 4 Series should also be able to handle long distances.
We tried earlier on a free stretch of motorway. Check. Even at 250, the coupé drives precisely in a straight line, leaving the driver alone. On the country road, on the other hand, when you turn the steering wheel, you can feel that something is happening, that the 4 Series does not soberly implement a desired direction, but likes curves. Not angular, not hectic, but willing. But there are differences: where the 440i xDrive with all-wheel drive and adaptive dampers tends to turn in full and stay neutral, the 430i whizzes through corners with more jaggedness.
Take it easy: 430i
Why? Lower front axle load, rear-wheel drive including electronically controlled limited slip differential plus sports suspension. In this way, it makes smaller bumps more tangible than the M440i. Otherwise, the 430i also basically remains supple, to which the stroke-dependent dampers also contribute. You came with the current 3 Series, working at the front in the pulling direction, on the rear axle in the pushing direction with a second piston and progressive tuning depending on the spring travel.
Which would clarify the matter with the more intense aroma of the 4 Series, right? Even in two flavors. Even if today without a maid in plaster.