BMW M2 Vs M240i: Six Crucial Differences

As soon as the BMW M235i was replaced with the M240i, keyboard warriors across the world were asking the same question: why bother with the M2?

On the face of it, you can understand that rationale. The M240i actually has more torque (369lb ft vs 343lb ft, although an overboost function briefly bumps the M2 to the same figure), and the power difference has dropped to 36bhp. In fact, a comparison video (admittedly a not terribly scientific one) revealed the M240i to be faster at certain points, partly down to the M2 being around 100kg heavier due to all the extra meat in its suspension.

But as we like to point out time and time again, cold, hard facts and figures never tell the whole story in the world of cars. So, to find out where your extra £9000 goes when opting for the full-fat M Division car as opposed to the semi-skimmed M Performance machine, we pun an M2 together with the M240i for a detailed analysis.

1. Engine

If we were talking about the old M235i this would be much easier, because the M240i’s predecessor and the M2 share the same N55 turbocharged straight-six. Well, almost: the version in the M2 gets forged pistons, a forged crankshaft and additional oil cooling.

The death of BMW’s ‘35i’ cars has also spelled the end of the N55, with the newer ‘40i’ models (M240i, 340i, 440i and so forth) receiving the all-new B58 unit. It’s part of BMW’s new modular engine series, available in three, four and six-cylinder configurations each packing 500cc per cylinder. Keen maths enthusiasts should already have worked out that this means the six pots are 3.0-litre units, blown by a single twin-scroll turbocharger.

Sounds like an identical setup to the N55, but the B58 is actually bigger by, err, 1cc. But it’s more powerful than the old engine, and torquier too. Later on, BMW retired the N55-powered M2 and replaced it with the M2 Competition, powered by a detuned version of the M3/M4’s S55 twin-turbo straight-six.

2. Gearbox

Both cars get standard-fit six-speed manual gearboxes, and while the M2 gets a fancier linkage, the two transmissions feel much the same. And by that, I mean a tad rubbery, and not anywhere near as good as the slick six-speeder in the Porsche 718s. Both the BMWs get an auto-blip feature too, although the M240i’s seems to only rear its head during more spirited driving.

Where there is a big difference though is with the automatic versions: the M240i makes do with an eight-speed ZF-sourced ‘box, while the M2 gets a seven-speed M Division dual-clutcher lifted from the M3/M4 brothers.

3. Suspension

If you’re really into driving, this is the most important point here. The M2 gets front and rear subframes pinched from the M4, with a track that’s 63mm wider at the front and 69mm wider at the rear compared to the M240i. It sits lower on stiffer springs, there’s beefier bracing between the suspension towers, and there are no suspension bushes at the back whatsoever. Instead, the rear subframe is attached directly to the body, upping stability and stiffness at the expensive of comfort.

Curiously, the M240i can be specced with adaptive dampers, something you can’t option on the M2.

4. Differential

Here’s another biggie. The M2 gets an electronically-controlled, multi-plate limited slip-differential that’s able to send up to 100 per cent of power to either rear wheel. It’s clever too - how it operate depends on steering lock, throttle position, brake pressure and yaw rate.

What goes on at the back of the M240i is a little less sophisticated: you get an open-differential, and that’s it. As we’ll explain later, that’s a bit of an issue giving all the power which is sent rearwards.

5. Brakes

Both cars get four-piston callipers at the front and two-piston jobbies at the rear, but the discs are slightly larger on the M2. They’re drilled too on the latter car too, and the brake hubs are made from aluminium.

6. Bodywork

The M2 has a set of dramatically widened wheel arches to accommodate the wider track, and my, does that make a difference to the car visually. The M240i looks weedy in comparison, and its 18-inch wheels are dwarfed by the 19-inch rims on the M2 with their slight tyre stretch.

The M2 also gets a different front bumper to aid cooling but also aero, with the ‘air curtains’ on the outer edges working with the new arches, side skirts, rear diffuser and small boot spoiler to reduce high speed lift by 35 per cent while cutting drag compared to the regular 2er.

How do they drive?

So, that’s all the technical stuff out of the way, but what about the feel of these cars?

I drove the M240i immediately after a few days in an Audi R8 Spyder, providing a decent way to ‘cleanse’ my automotive palate with something entirely different to the M2. And even after a bout of bombastic V10 power, the M240i feels exceptionally quick.

There’s an enormous amount of clout in the mid-range, and you never really need to rev the engine out. It sounds slightly different its N55-engined predecessor, but it still isn’t an especially sweet-sounding six-pot.

The M240i is a very capable and entertaining B road weapon, but you do get the feeling it’s skirting around the boundary of what its more basic chassis is capable of taking, and - depending on the conditions - a little over it. The lack of limited-slip differential means it doesn’t feel awfully comfortable when you lose grip at the rear (we’re in one-tyre-fire country here, boys), something you’ll find happening fairly often with that fat serving of mid range torque. The brakes could do with being stronger, too.

Back in the M2, I immediately discovered that all those changes detailed above amount to completely different car. You get the kind of confidence in the corners that the M240i just can’t deliver, with a keener turn-in and far less body roll. Thanks to a properly sorted limited-slip differential, it’s far grippier, and has a much more controllable attitude when you nudge past the limit. The M240i’s open rear diff really is its Achilles heel, and the optional (at dealer level) £2500 LSD is seriously worth considering if you buy one of these.

The performance is a tricky one, as the M240i does actually feel quicker thanks to the beefy torque delivery. But the M2’s old N55 is much more enjoyable to use: it’s more responsive, and a lot reviver. In the M240i you’ll rarely find yourself changing above 6000rpm, whereas the M2 is much happier being smashed into the rev limiter.

Conclusion

For its £35,090 asking price, the M240i is unquestionably an utter bargain. To give similar straight-line performance to the M2 and even more expensive sports cars like the Porsche 718 Cayman S plus an engaging drive for that kind of money is impressive.

But I wouldn’t call the M240i an out-and-out sports car. ‘Fast coupe’ seems like a much more appropriate description. The M2 on the other hand? Hell yeah, it’s a sports car.

The gap in straight-line performance is awkwardly slim now, to the point at which there’s preciously little difference between the two. But it is worth pointing out that we’re comparing a car that’s had it’s mid-life update to one that hasn’t - the M4-engined Competition does a great job of redressing the balance in terms of performance and drama, admittedly bringing with it a weight increase.

Even with the straight-line performance similarities though, the original M2 more than justifies the premium over the ‘lesser’ M240i. It’s an entirely different feeling car, it’s far better looking and more lustworthy thing with all that muscular bodywork, and the draw of having a proper M Division car rather than an M Performance pretender cannot be ignored.

Which would you go for, if you had the cash?