Dinan S3-R BMW 1M Coupe

Wed, 02 Apr 2014

I nearly shed tears a few years ago upon learning that BMW was only planning to produce a very limited quantity of its then-new 2011 1 Series M Coupe. In simplest terms, the two-door was a 1 Series fitted with a modified version of the automaker's twin-turbocharged 3.0-liter inline-six, and the running gear (gearbox, driveshaft, axles) from contemporary M3 models. It was also a return to form for the brand. Aggressively short and stubby in stature but packing telltale flared wheel arches that hinted at its potential, the four-seater was a spiritual successor to the original (and much loved) E30 M3 from decades earlier.

After spending a day with the original high-performance 1 at New York's Monticello Motor Club, I declared, "The little coupe with the big flares is old-school retro cool and deliciously fun to drive ... the new BMW 1 Series M Coupe doesn't target boy-racers, it targets enthusiasts." Yet sadly – and despite strong demand – BMW limited the model's production to just one year. All told, only 740 units made it to the States, and each was gobbled up at a starting price of $46,135, a price tag history will show to be a bargain.

Since I had little hope of even driving one again, I deliberately pushed all memories of BMW's 1 Series M Coupe from my mind – until my phone rang recently. On the other end was a representative from Dinan Engineering who wanted to know if I would be interested in driving the company's new S3-R BMW 1M. A quick Google search revealed it to be a heavily modified version of the discontinued 1 Series M Coupe. As if they needed an answer...

Dinan prides itself on its meticulous engineering.

Dinan Engineering is well known and well regarded as a BMW tuner, yet it doesn't want to be associated with the dozens of other shops who tinker, tweak and piggyback upgrades on Bavaria's finest. Instead, the company prides itself on its meticulous engineering. The California-based outfit deciphers factory ECU codes and then spends months improving the programming to create tunes that deliver reliably better performance. But it isn't just a software company – Dinan has been engineering parts, building engines and supporting factory racing programs for decades.

A discontinued, limited-production 2011 model is admittedly an odd choice for an expensive new development program, so I asked Steve Dinan why he had selected the 1 Series M Coupe. "We developed the car because we wanted to develop the larger turbochargers for the N54 engine and needed a platform. These large turbochargers will fit on any [model equipped with the] N54 engine ... we really like the 1M at Dinan and it sounded like a really fun project." With two small turbochargers and direct injection, the all-aluminum N54 was used extensively by BMW from 2006-2008, in 3 Series sedans, wagons, coupes and convertibles. It was also dropped under the hood of the X6, Z4 and the 1 Series – it's a popular engine with enthusiasts.

This triple-black coupe has a timeless, if upright, BMW appearance.

It may be a few years old already, but this triple-black coupe has a timeless, if upright, BMW appearance. Those unfamiliar with the factory offering may accuse Dinan of bolting on more than a few gaudy aero bits, but the aggressive front splitter, fender flares and rear fascia are all 100-percent stock pieces from the 1 Series M Coupe. Aside from the wheel/tire package, Dinan's only exterior add-ons include the carbon fiber mirror caps, carbon fiber rear spoiler and a chrome "DINAN" logo on the rear decklid. Inside, the cabin has barely been touched, with Dinan showing restraint by only installing its own floor mats, aluminum pedal pads and a discreet serialized plaque.

Pressing the start/stop button immediately spins the 1M's engine to life. In stock form, the 1M arrived with a twin-turbocharged 3.0-liter inline-six (internal code N54B30T0) tuned to deliver 335 horsepower and 332 pound-feet of torque (an "overboost" function increased turbo pressure to allow 369 pound-feet for brief periods of time). Dinan chose to retain the fit larger turbochargers, a high-capacity oil cooler, bigger air-to-air intercooler, free-flow exhaust and increased boost to generate 444 horsepower and 450 pound-feet of torque.

The sound emanating from the quad pipes is aggressive, but it never crosses into the realm of annoyance.

Even at idle, the sound emanating from the S3-R's slightly larger quad pipes hung below the real valance is aggressive, but it never crosses into the realm of annoyance. Dinan is justifiably proud that its stainless-steel exhaust systems are all but free of the irritating drone and resonations common in the aftermarket world. The system's mellow demeanor under light throttle means you can sneak out of the driveway for an early-morning canyon run without waking the neighbors, or your significant other – ask me how I know.

Someday, the automotive world will look back at BMW's slick-shifting, short-throw, six-speed manual gearbox (the only transmission offered on the factory M Coupe) and recall it as being one of the best of its type. In fact, why wait to appreciate? I grasped its leather shift knob with my hand, smiled, and flicked through the gears gingerly as the crankcase oil warmed. As I directed the black BMW slowly across town, I came upon a Toyota Prius, whose pace demonstrated that the driver was not in any hurry (as if they ever are), so I settled in a safe hundred feet behind its Kamm tail. In this mild-mannered state, the smooth six-cylinder engine proved completely docile – it's all but impossible to tell it's a tuned engine – and it purrs without a hiccup or stutter. In is, for lack of a better description, as pleasant as a typical BMW 1 Series.

The automotive world will look back at BMW's slick-shifting, short-throw, six-speed manual gearbox and recall it as being one of the best of its type.

The ride, meanwhile, is firm and definitely more aggressive than stock, but that's to be expected – Dinan has swapped out most of the suspension's underpinnings with high-performance components of his own design. All four corners of the 1M wear the company's adjustable coilover struts and springs, accompanied by a lightweight tubular adjustable front anti-roll bar, Dinan spherical monoball front bearing and precision rear toe links. The coilovers are adjustable for ride height (which helps lower the roll center), and the hollow tubular roll bar saves weight. The new front bearings, and rear toe links, allow precise suspension tuning while removing the factory rubber bushings to improve response. On the LA Basin's relatively polished roads, these new components do their job inoffensively, and there isn't a single squeak, rattle or rumble from the chassis.

With the oil toasty (kudos to BMW for fitting an analog oil temperature gauge on the dashboard), and the roads empty, I slow to a crawl and disabled Dynamic Stability Control (DSC) to see what a 3,350-pound car with 444 horsepower is really capable of. Slamming the throttle down hard from a slow, in-gear roll immediately rips the tires from the pavement. Once they hook up, shifting into second again breaks them free anew. Even third gear os prone to shredding 1M's wide tail-end rubber. Throttle response is near-instant and almost completely free of turbo lag (a known N54 strength). The resulting acceleration makes the 1M feel quicker than a Chevrolet Corvette Stingray or a Porsche 911 Carrera S.

"Top speed should be around 180 mph." – Steve Dinan

The stock 1 Series M Coupe will crack the 60 mph benchmark in about 4.5 seconds, a very quick sprint in today's automotive world. Nobody reputable has hooked the Dinan S3-R 1M to accurate test gear yet, but based on my drive, I wouldn't be surprised to see it shave nearly a second off the stock car's time. And, while the standard 1M is capped at 155 mph, this coupe is not restricted. "Top speed should be around 180 mph," Steve reports. "I have personally driven it that fast," he adds, proudly.

As would any warm-blooded enthusiast, I headed straight for the mountains to test the 1M's agility. The factory put sizeable rubber on its 1 Series M Coupe (245/35ZR19 front and 265/35ZR19 rear), but Dinan has bumped wheel widths up by a half-inch both front and rear, thanks to its Dinan-branded BBS CH-R cast alloys. As a result, the company has been able to squeeze 275/30R19 and 295/30R19 Michelin Pilot Super Sport summer tires into the wheel wells. This steamroller rubber makes its presence known with a road surface rumble, a noise that is especially pronounced on coarse pavement, but their sizeable footprints deliver the goods when the road starts to snake.

All of the things that made the factory 1 Series M Coupe so special have been amplified in the Dinan. Setting up for a corner is effortless, as the BMW's tall "gentleman's" seating position provides a panoramic view out of the greenhouse. Diving into corners reveals a firm brake pedal, with nary a hint of fade regardless of how much is asked of the E92 M3's stopping package (these may be the best single-piston calipers on the planet). Turn-in is sharp, with only the slightest bit of understeer – I'd almost call its handling completely neutral. Most impressively, the chassis responds immediately to the throttle, as the two-door eagerly blasts out of each corner fighting for grip. This harmonious balance of acceleration, braking and cornering ability is stunning. As a total package, the Dinan 1M is breathtaking.

This harmonious balance of acceleration, braking and cornering ability is stunning.

While playing in the mountains, I quickly learn that there are a couple of buttons on the 1M that must be pressed each time the coupe is started. The first is the "M" button, on the right spoke of the steering wheel, which switches the accelerator pedal to a more aggressive engine map that improves throttle response. The second is the "DSC" control button at the center of the dashboard. Holding it for a few seconds initiates "M Dynamic Mode," a sportier setting that allows more wheelspin and slight tail-out drifts before the electronic nannies kick and save the paint (I experimented with disabling the DSC completely in the canyons, but it allowed too much wheelspin, hampering forward progress). Ignoring both of those actions severely cripples performance and driver enjoyment – there's no nice way to put it.

Most tuner cars have a one-track mind and often solely focus on speed. But carving canyons quickly isn't the 1M's only talent. I would drive Dinan's little toy for three glorious days, incorporating it into my family's routine, something I try to do with every press car. Despite its diminutive appearance, its cabin is surprisingly roomy thanks to its upright roofline. I sat four adults within its confines, and the only challenge was limited backseat knee room behind tall drivers. The trunk is accommodating, and the back row of seats split/fold to improve utility. During one 100-mile round trip on the highway, the on-board computer claimed I was averaging 30.1 miles per gallon – particularly impressive considering the EPA rates the stock 1 Series M Coupe at just 26 mpg on the highway.

I consider Dinan's little coupe one of the best street cars that I have ever driven, but there are a couple of small dings on its report card.

I consider Dinan's little coupe one of the best street cars that I have ever driven, but there are a couple of small dings on its report card. Every time I pushed the 1M hard, I found myself cursing its tires. While the Michelin Pilot Sport Cup tires are a wonderful high-performance upgrade for most sports cars, their UTQR treadwear rating of 300 tells me the rubber compound is too hard – and all of the S3-R's inadvertent sideways action drives the point home. If it were up to me, I'd wrap nothing with a treadwear rating above 140 around its alloys (taking it one step further, R-compound rubber would make this little BMW a giant slayer). I would also swap out the stock drilled rotors, which make a hole-induced whirling racket under hard braking, with some solid or slotted ventilated units. Along that note, Dinan offers a Brembo upgrade kit, which wasn't fitted to my test car, but I don't think it's necessary.

BMW is just days away from allowing enthusiasts to drive its all-new F82 M4, a model that utilizes an M-modified single-turbocharged inline-six (S55B30). We asked Steve how the Dinan 1M will likely compare to the factory offering. "The 1M will be a little faster than a stock M4, but once the M4 is modified, it will be a lot faster ... a faster factory car will almost always yield a faster aftermarket car because of the inherent qualities and equipment that the factory bakes into the car." As expected, Dinan is eager to work its engineering magic on the upcoming M3/M4.

It was so fully formed and well-rounded that it felt like BMW itself had made it.

I'm not one who typically raves about modified cars, as aftermarket tuners often focus all of their attention on one aspect of performance (i.e. highest top speed or quickest 0-60), which results in unbalanced, as the rest of the vehicle isn't up to the challenge. Even worse, many aftermarket modifications are temperamental or unreliable, enough for me to want to exercise specific care or hold back during spirited driving. But that wasn't the case with the Dinan S3-R. They dropped it off with a smile and told me to enjoy it, offering no special precautions. I took their advice and proceeded to drive the snot out of it. Regardless of what I threw at it – or how hard I tossed it – it never skipped a beat. It was so fully formed and well-rounded that it felt like BMW itself had made it.

As an automotive enthusiast who craves a powerful, balanced and engaging driving experience, I am absolutely smitten with this little black coupe. BMW built a near-perfect car in 2011 with its 1 Series M Coupe, but the determined team at Dinan Engineering has demonstrated that it can indeed polish and improve a masterpiece.

Vital Stats

Engine:: Twin-Turbo 3.0L I6
Power:: 444 HP / 450 LB-FT
Transmission:: 6-Speed Manual
0-60 Time:: 3.8 Sec (est.)
Top Speed:: 180 MPH (est.)
Drivetrain:: Rear-Wheel Drive
Curb Weight:: 3,350 LBS (est.)
Seating:: 2+3
Base Price:: $50,000 (Est. Donor)
As-Tested Price:: $66,719

By Michael Harley