Sibling Rivalry: Comparing BMW's M4, M2 and M235i

By Tim Suddard
Mar 26, 2018 | BMW | Posted in Features | From the Nov. 2016 issue | Never miss an article

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When the BMW M235i came out two years ago, we fell in love. Instantly, we decided we had to have one. Here was an M-car aimed right at us: compact, fast, attractive, and with a starting price below $50,000. It was even decent on fuel.

We got one in the form of a loaner from BMW, and we had the company’s blessing to modify and run the car for a full year. We shed a tear when it went back to the mothership.

BMW’s lineup has changed a lot since the M235i’s debut. The brand released the M3 sedan and similarly equipped M4 coupe to rave reviews, and this spring it quietly introduced a smaller sibling called the M2.

Is this M2 coupe really the one to get? Does it push the M235i to also-ran status? Can it outshine its bigger brother, the M4? What if the M2 is a bit of an overachiever outfitted in upgrades from the M Performance Parts catalog? We headed to the BMW Performance Center in Greer, South Carolina, to see how these M-cars stack up.

The Site

The BMW Performance Center is basically a theme park of different driving conditions and course configurations. We used two of them for this comparison.

First we familiarized ourselves with the cars on the facility’s big loop. Then we recorded lap times on a sub-30-second circuit known as the short course. It can be described as a very fast autocross course or a very condensed race track. Elevation changes, an 80-plus-mph top speed, and a mix of tight and fast turns make it a fun, safe place to test street cars.

Access to this facility isn’t limited to industry insiders, either, as the BMW Performance Driving School teaches a full slate of courses aimed at teens, performance addicts and the general public. It also offers classes on both on- and off-road motorcycle riding. Looking for a sampler platter of sorts? For $299, the school offers a 2-hour program that puts participants behind the wheel of several different BMW products.

The Drivers

Our drivers included this author, Tim Suddard; Mike Renner, BMW Performance Center employee and one of its lead test drivers; and James Clay, longtime IMSA pro hotshoe, BMW Club Racing driver, and owner of BimmerWorld. Although we gathered driving impressions from everyone, we kept the hard data simple by using only James’s very consistent lap times.

The Cars

When we got our M235i, we thought it was the ultimate compromise–and we mean that in a good way. It balanced strong performance with good fuel economy at a fair price.

Then the M2 came around and, quite honestly, shattered our fascination with the M235i. The M2 sports a base price of $51,700–and we know, that’s a lot of money for us, too. But add some of the M2’s standard equipment to our beloved M235i–things like navigation, heated seats and an upgraded sound system–and suddenly the price difference is only a few thousand dollars, if that.

Then there’s the host of performance upgrades that separates the M2 from the M235i: bigger brakes, stiffer suspension, bigger wheel-and-tire package, and another 45 horsepower. At 3450 pounds, the newer car actually weighs 55 pounds less than the M235i. And in typical M fashion, the M2 sports more aggressive flares, spoilers and markings.

One of our favorite M2 features has to be the active, electronically controlled limited-slip differential. The M235i comes standard with just an open differential, but for a few grand you can replace it with a dealer-installed M Performance limited-slip unit. It’s not the same as the M2’s, however, even though both are clutch-type diffs. Depending on traction requirements, the M2’s differential can deliver zero to 100 percent lock-up. The M235i’s offers up to 30 percent lock-up on acceleration and 9 percent on deceleration.

Speaking of awesome M2 features, the next car in our test is crawling with them. Mike Renner’s six-speed M2 just won its class in the gruelingly fun Tire Rack One Lap of America presented by Grassroots Motorsports. The car was once part of BMW’s driving school fleet, but now it’s a lesson in how M Performance parts installed right at the dealership can crank up the model’s fun quotient.

The major upgrades are a coil-over suspension kit and sport exhaust system. A carbon-fiber splitter, diffuser and rear spoiler add track-ready looks and a bit of downforce. Even the mirror covers are carbon fiber.

And then there’s the M4, the two-door variant of the M3 sedan. The M4 measures about a foot longer and bit wider than the 2 Series. While the M2, M3 and M4 are powered by essentially the same drivetrain, the M4 is tuned to produce 425 ponies. That extra size and power comes with a bigger price tag: $65,700 before adding any options.

The Numbers

Specs are one thing, but what does the stopwatch say? Time to analyze James Clay’s timed laps on the short course.

But first, a quick caveat about tires: Our test cars weren’t all wearing the same kind. The M2, M4 and One Lap MR2 ran on the stock Michelin Pilot Super Sport, a summer tire. But the M235i, which we borrowed from the BMW Performance Driving School, wore the program’s spec rubber: the Continental ExtremeContact DWS. As an all-season tire, it simply couldn’t match the Michelin’s track performance. We factored this disadvantage into our analysis.

Case in point: When the M235i, the former darling of the BMW lineup, averaged 28.474-second laps, we thought it was capable of more. Swapping to the Michelins could have dropped another second from its average lap.

The M2 turned an average time of 26.664 seconds. Never mind the increased horsepower; the better wheels and tires and the tighter suspension made a world of difference on their own. And then there was that limited-slip differential. When leaving the off-camber hairpin, the M2 happily dug in and launched down the following shoot.

The M4 did beat the M2, but just barely, averaging 26.524-second laps. The increased size and weight of the M4 was offset by a bit more power, and that made the slight difference.

The winner of the day, though, was the One Lap M2. It posted an average lap time of 25.944 and sounded simply amazing while doing so thanks to its M Performance exhaust system. The M Performance coil-over kit also transformed this car and made it a track terror without ruining the ride quality. Usually we look to the aftermarket for suspension pieces, but BMW has done a fantastic job designing and building this track-ready kit. It doesn’t allow for camber adjustment, unfortunately, but the One Lap M2 didn’t seem to need it to perform admirably.

The Preferences

Choosing a winner isn’t just about the lap times, though, especially when they’re this close. This author personally prefers the smaller M2. It costs less money, delivers amazing performance, and feels more nimble.

At 6-foot-5, James is more comfortable in the M4’s cockpit. He also notes that the short course benefitted the M2 in this test. He believes that on a long track like VIR or Road Atlanta, the M4 would have trounced its little sibling.

Mike, who drives BMWs every day, says he loves them all. When pressed, though, he admits that the M4 is an amazing street and track car.

The Conclusions

There isn’t a loser in this bunch, and BMW’s M Division is back on point. Its current lineup will simply knock your socks off–on the street or on the track. And long gone are the days of M-cars retailing for nearly twice as much as their standard-issue versions. Competition–or a conscience–has put M-car pricing in line with the rest of the field.

So, which one to get? James would take the M4 and tear up a track like Road America. Make ours an M2 with the M Performance suspension and let’s go autocrossing. For an M2 that can tackle a full plate of competition challenges while still remaining street-friendly, throw in the exhaust system and aero package–if you have the scratch.

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View comments on the GRM forums
Klayfish PowerDork
3/26/18 2:16 p.m.

I got to do the same driving experience at the BMW facility in 2016.  First, we got to do the offroad stuff in an X5, which was a lot of fun.  Next was an autox course in an M235i, which was a hoot.  Then we did the short course like you did.  We got to run the M4, M235i, Z4, M5, X5M.  Ran each of them for a solid 6 or 7 laps.  No instructor in the car, we were free to hammer away as hard as we wanted.  All of the electronic nannies were on, so it cut into the fun a bit, but I still got to really hoon them.

All I could say was holy E36 M3 on a donut!!!  I had a smile on my face for weeks after that.  It's as much fun as you can have with your clothes on.  My personal favorite was probably the M4.  But the M5 was simply amazing for a large sedan.  Like you mentioned in the article, it was easy to hit 80mph at the end of the "front straight", especially in the M4 and M5.  That's incredible, considering how short the straight really is.  Thrust like a booster rocket.  As for the SUV should be that fast or handle like that.  It's silly...silly awesome.  I walked away with a love for how BMWs drive.  Just awesome, simply awesome.

Jaynen UltraDork
3/26/18 2:51 p.m.

And the crazy thing is I think you could tow the others to the track with the X5M as well

LanEvo HalfDork
3/26/18 9:15 p.m.

Got to run the M3, M4, and M2 back-to-back at Lime Rock last year. The M2 was the most playful by far. Felt like a proper M-car of old. Did whatever you asked it to. Very neutral.

The M3 wasn’t far behind, but the M4 was just weird. I couldn’t balance it anywhere near the limit. Total 7/10ths car ... which is weird for a BMW

mcompact New Reader
3/27/18 2:46 p.m.

I bought a fully optioned CPO M235i a couple of years ago; at the price it's hard to beat- although I'd probably take an M2 if I had the scratch.

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