Is BMW’s new M3 sedan really just a BMW M4 with two more doors? We tested both cars back-to-back in Singapore to find out

SINGAPORE — Here’s the thing, the four-door M3 Competition sedan driven here and two-door M4 Competition coupe are technically, mechanically identical. It’s really unnecessary to re-state the specifications for the M3 Competition, because the two cars share the same six-cylinder, twin-turbo engine, same gearbox, same chassis, and even same tyre and wheel sizes. A close inspection of the data shows that even the eight forward ratios in the gearbox and final drive ratio are identical. 

The only real difference that is visually discernible, besides the fact that the M3 has more doors, is that it’s also a tiny bit wider and taller. About 20mm wider and 40mm taller, to be specific. And the M3 is just 5kg heavier despite the additional two doors. 

Then why, despite the mechanical similarities, does the M3 feel like a different car to drive? The view from the driver’s seat is the same from both the M3 and M4, but the feedback coming through to the driver is actually quite different. The M3 Competition actually feels a little bit more pliant and softer, though in typical M car terms, not by very much. It’s the kind of difference that is readily felt when you hop from one car to the other right away, but if taken individually it can get quite hard to pinpoint what the difference is exactly.

The last time BMW made a limited edition M3, it was this one

The M3’s exhaust is also a little less raucous than its coupe sibling, but still packed with character and everything that is true about the M4 is also true for the M3. It has that ability to attack corners with plenty of gusto, and its straight line acceleration is a pretty good visceral kick every time you plod the accelerator. 

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In typical Germanic tradition, BMW calls the M3 a little less ‘extroverted’ than the coupe, though with both cars sporting that dramatic new front end from the 4 Series that’s been discussed to saturation it’s hard to think of the M3 as the ‘quiet’ one. While the M4 already has very usable rear seats, passengers in the rear bench of the M3 will be a little bit more comfortable, thanks to the marginally increased head and legroom. 

Also, continuing with the theme of being more practical, the M3 has a 480-litre boot space compared to the 440 litres in the M4. 

What we can garner from the drives we had in the cars is that the cars do have slightly different suspension tuning, though this has not been officially confirmed by BMW. The bottom line is that M3 feels more comfortable as a daily driver. While it’s not as plush as the larger M5 sedan even with the sport modes switched off, it rides a little more comfortably over street bumps compared to the ever so slightly stiffer M4.

This is the BMW M3’s arch-rival

That’s not saying that the M3 Competition is soft however, just that it’s been tuned slightly differently. We think that given a clean race track and identical tyres, both cars will produce identical lap times once a good driver adapts to their individual characteristics.  

They’re both priced within a whisker of each other, with the M3 Competition costing just S$5,000 less than the M4 Competition. In the mid S$400k price bracket that is nearly no difference, so whichever car you buy is pretty much down to how much you prefer the idea of owning the M3/M4 as a coupe, or how much you really want a more practical sedan.

BMW M3 Competition