2013 BMW 3-series

2013 BMW 3-series

As we inch closer to the 2012 launch of the sixth-generation BMW 3-series, code-named F30, more details emerge—along with better spy shots. The photos seen here reveal a compact sedan that, visually, remains close to the current model: The proportions are virtually unchanged, and, with the tape-covered front and rear lights, it takes an expert to spot the differences.

Specifically, the lower body side gets a more-pronounced crease, which is picked up by the rear bumper. Somewhat surprisingly, one of the two cars captured here carries a regular sunroof, not a panoramic one, as has been BMW’s fashion of late. Prominent changes will be made to the front end, with the next 3er getting a less-convoluted headlight design. And inside, the dashboard will lose the bump above the optional navigation screen. The interior of this 3 will stay in the mold of the previous generations; there is none of the radical "layered" styling that was introduced with the Efficient Dynamics concept and which will trickle down to the series-production i8.

More interesting are the new 3’s technological changes. The next generation will remain rear-wheel drive with an optional all-wheel-drive system, but it will be powered by an entirely new family of engines, all of them turbocharged. BMW will offer four- and six-cylinder diesel and gasoline engines. This forced-induction mantra applies to the next M3 as well, which will receive a 400-plus-hp inline-six. Available transmissions across the lineup will include a manual, a torque-converter automatic, and a dual-clutch automatic.

BMW also is working on a three-cylinder engine, which could find its way into the 3-series. A hybrid 3-series is planned, too—but unlike the three-cylinder unit, it’s being created with the U.S. market in mind.

The four-door sedan will continue to be the most important model, but this time around, BMW is going after every possible niche with additional body variations. BMW will offer a station wagon, a "Gran Turismo" five-door hatchback, a two-door coupe, a folding-hardtop convertible and, at least according to rumor, a real softtop convertible as well.

The BMW 3-series is the company's core model and the benchmark for sports sedans around the world. BMW must try to stay ahead of the game in terms of handling, fit and finish, and sheer driving excitement. The mildly revised shape is a good sign—let’s just hope BMW doesn’t mess with the rest of the recipe too much.

2014 BMW 3-series GT

2014 BMW 3-series GT

Take a car like the Mercedes-Benz CLS or Volkswagen CC, stretch the roofline a little farther back so that the backlight incorporates into the trunklid and forms a hatch, and you’ve got a body style that is booming on the other side of the Atlantic. The sleek Audi A5 Sportback is a huge hit, and even the stylistically challenged BMW 5-series Gran Turismo has exceeded BMW’s expectations. That surely pleases the company's bean counters, if not people who spot the car on the street.

Now BMW is taking the idea one segment down-market—and, thankfully, taking a cue from Audi on styling direction. The 3-series Gran Turismo spotted by our spy photographers looks little like its big brother, being closer in size and proportion to the A5 Sportback. Although the camouflage exaggerates the height of the rear end, notice the notch in the camo indicating the location of a small spoiler above the taillights. The roofline is low and sleek, and the bulging hood adds tension to the body.

Like the other 3-series body styles, the GT will have standard rear-wheel drive and optional all-wheel drive. A clever mix of materials should keep weight from rising too much, but it remains to be seen whether or not BMW can emulate Audi's success in slashing hundreds of pounds from its next-generation vehicles. BMW’s work with carbon fiber will first benefit its upcoming electric cars, whose other expensive technologies and low sales goals make the cost of the material more palatable.

Act Now, Before They’re Gone Forever!

If you still care to drive a 3-series with the legendary, naturally aspirated inline-six, the Gran Turismo—or, for that matter, any 3-series based on the new F30 platform—will not be for you. All engines in the next 3-series family will be turbocharged, with four-cylinders covering the landscape below 300 hp and a blown inline-six taking over above that. This new family of engines might include three-cylinders, although the upscale aspirations of the GT means they are unlikely for this car. Diesels are a given, however, and so is a hybrid version. Power will be transmitted through a six-speed manual gearbox or an eight-speed automatic.

For a kind of entertainment other than that provided by the powertrain, BMW promises its upcoming vehicles will be leaders in connectivity. Surfing the web, making phone calls, having text messages read aloud, and downloading music will keep drivers informed, busy, and distracted.

The GT will join a large family, complementing the 3-series sedan, station wagon, coupe, and folding-hardtop convertible. And that’s a family it won’t just be joining in Europe. The 3-series Gran Turismo is likely to be sold in the U.S. as well, where—since Audi doesn’t sell the A5 Sportback here—it will pretty much have the niche to itself. The 5-series GT also has a niche to itself, but we’re pleased that the 3’s looks to be a much shapelier segment.

BMW, Dinan Supercharged S3-R M3

BMW, Dinan Supercharged S3-R M3

Steve Dinan has been modifying and upgrading BMWs for so long and so successfully that his services and products are available nationwide at select BMW dealers. We admire his work for the way in which it amplifies the essential flavor of the cars. We like BMWs, and the stronger they are, the better we like 'em.

Which makes this M3 conversion an exceedingly tasty concoction, because the stock product was so closely focused on sporty attributes in the first place. When skillfully enhanced with more power, better handling, stronger brakes, and a more forceful sound, it is a heady cocktail.

And like most strong cocktails, the price is steep. The intercooled supercharger system Dinan developed for the M3 is listed at a fairly breathtaking $17,999, and that doesn't include the free-flow exhaust system ($1699) or high-flow throttle bodies ($1199). Dinan defends the price structure by explaining that the development exercise for a car of this caliber is a long, difficult, and expensive process, one that must be repeated each time BMW brings out a new model.

Considering just the electronic side of the project, here are some of the things that have to be recalibrated: the top-speed governor, the throttle-by-wire system, the Double VANOS cam timing, the intake-air temperature, the ignition timing, and the air-fuel ratio. Many of those variables require calibration at nearly every conceivable combination of rpm and load points. Among the important hardware additions of this conversion is a Vortech supercharger that produces 5.5 pounds of boost through a large air-to-air intercooler.

A cold-air intake system and larger-capacity fuel injectors join the team to increase engine output from the car's stock 333 horsepower to a claimed 462. Torque rises from 262 pound-feet at 4900 rpm to 328 at 5500 rpm, says Dinan. These are increases you can feel at the seat of your pants at virtually any engine speed, and they put the M3 in the same league as Audi's RS 4 Quattro and Mercedes-Benz's C55 AMG when it comes to throttle response.

We all know the BMW home office has a new M3 in the works, based on the excellent 3-series we've recently sampled ( C/D, September 2005), and the general expectation is that it'll be powered by a V-8 engine to match those of the aforementioned competitors. In the meantime, Dinan can offer comparable performance with the current six-cylinder car.

To reconcile these higher power levels to the car's handling, the S3-R M3 chassis has been retuned with Dinan/JRZ adjustable shocks, performance springs, an adjustable front anti-roll bar, negative camber plates, and toe-deflection-limiting bushings. The result is a car with tenacious roadholding, instant responses, progressive breakaway characteristics, and taut ride-motion control.

We drove this car along our favorite canyon road at speeds that approached race pace, and at no time did the car ever feel close to the ragged edge. Surprisingly, the ride comfort is, if anything, better than in the stock car. Only on high-frequency surfaces did the Dinan undercarriage utter a skateboard-like resonance. Everywhere else it swallowed surface imperfections with well-mannered gulps. That's quite an achievement on 19-inch Michelin PS2s with 30-percent aspect ratios mounted on lightweight forged alloy wheels that helped the S3-R pull 0.92 g on the skidpad, 0.05 g better than the stock car.

To match the rest of the car's expanded performance envelopes, Dinan fits 15-inch Brembo rotors behind the front wheels, clamped by four-piston calipers using Ferodo pads, and pressurized by stainless-steel brake lines. The rear wheels get 13.6-inch rotors but are otherwise similarly equipped. As one might expect with this hardware, braking is strong and fade-free, with a firm and communicative pedal feel.

This is a fabulous car to drive, in every way, and our only regret is that the day we tested it, the ambient temperature was 100 degrees at 8 a.m. We use elaborate weather-correction disciplines, of course, but the S3-R M3 has an air-to-air intercooler that wasn't very effective at removing intake-air temperature when it had 100-degree ambient air blowing by it. Consequently, we don't think the Dinan was making full power. It ran to 60 mph in only 4.4 seconds (stock: 4.8 seconds) and through the quarter in 12.9 seconds at 112 mph (stock: 13.6 at 105). Those numbers are worthwhile improvements, but we think the S3-R would be quicker on a cooler day.

Acceleration statistics tell only a part of the story. The Dinan feels like a 462-hp car in all driving conditions, with ample torque throughout the engine speed range. Throttle response is vigorous, providing strong passing performance without a downshift in almost every situation. Part of the car's bright response is due to the blower-boosted torque, but the S3-R also wears shorter final-drive gearing. A 3.91:1 limited-slip differential replaces the stock 3.46:1 unit. Because of the shorter overall gearing, Dinan raised the rev limit to avoid a second-to-third shift before 60 mph to hasten that benchmark achievement.

Dinan's retuned exhaust system has eliminated the strangely tinny tones that afflict the standard car at some engine speeds, replacing them with a melodious baritone that is emphatic without being overbearingly loud. This car's voice is now as authoritative as its performance. Although that performance may not come cheap—our test car rang in at almost $100,000—the S3-R is exclusive, fast, and fulfilling.

BMW, Dinan S3 BMW 335i

BMW, Dinan S3 BMW 335i

The car you see here was no doubt envisioned by a legion of Internet dreamers—breathlessly commenting, “Crank up the boost!”—mere seconds after BMW debuted the twin-turbo 335i for 2007. But it took five Dinan employees hacking away at BMW’s software for a year and a half to finally make it happen.

It was worth the wait. Steve Dinan has sold more than 2000 software upgrades for the 135i/335i, making it the most popular upgrade in his company’s 31-year history. And it’s easy to see why: For $2199, a simple download at one of Dinan’s 129 U.S. dealers immediately endows a 335i with as much as 384 horsepower and 421 pound-feet of torque (versus 300 and 300, respectively). Dinan notes that this is actually more like a 60-hp gain, as BMW’s twin-turbo inline-six comfortably makes more than the advertised 300 horsepower in stock form.

The car tested here goes a little further. Outfitted in “Stage 3” trim, the S3 335i has an oil cooler that is twice as large as standard, a bigger intercooler, a better-breathing carbon-fiber intake, and a freer-flowing exhaust that allows for 1 additional psi of boost versus the 384-hp setup (14 psi total versus 8.8 psi stock). The result is 408 horsepower and a bombastic 440 pound-feet of torque. But it doesn’t come cheap: The aforementioned mods total $8895.

Not surprisingly, throttle tip-in is jumpy as the newfound torque introduces itself. The engine is crazy responsive from 3000 rpm but starts to run out of steam between 6000 rpm and the 7000-rpm redline—the boost tapers off in order to keep the turbos comfortably below their 230,000-rpm limit. And for a turbocharged engine, it still sounds remarkably raspy. At 4.4 seconds to 60 mph and 13.0 through the quarter-mile, the S3 335i is about a half-second quicker than a stock 335i in both regards and nearly matches the last manual M3 we tested.

But even more impressive than the engine work is Dinan’s $4225 chassis overhaul, which includes stiffer springs that lower the 3 by half an inch, adjustable Koni struts and shocks with Dinan-specific valving, front and rear anti-roll bars that mimic the M3’s, front camber plates, a carbon-fiber front strut-tower brace, and new bushings. Also add $5399 for 19-inch forged wheels—they weigh just 20 pounds apiece—plus Michelin Pilot Sport PS2s (265/30 front, 275/30 rear).

These mods make turn-in substantially more eager, and those front tires—40 millimeters wider—effectively squelch understeer. Hold on for 0.99 g on the skidpad—that’s superior to any M3 we’ve tested—and be ready to countersteer when the rear end comes around, jauntily.

Part of what makes the whole thing so exceptional is that, despite the dramatically increased performance, almost nothing is sacrificed except for a ride that’s more brittle and too harsh for our Michigan roads. But the steering is still linear, and nothing has been lost in the way that forces build up; there’s zero nervousness, dartiness, or tramlining; and, astonishingly, the tuned car even weighs 66 pounds less than our last stock 335i. Plus, the S3 335i meets 50-state emissions regs, and Dinan matches BMW’s four-year/50,000-mile warranty. In fact, we couldn’t help but think that Dinan’s chassis tune is probably closer to the BMW ideal. And that’s saying something.

BMW, Dinan S3-R BMW M3

BMW, Dinan S3-R BMW M3
Back in the 1970s, a collegian named Steve Dinan kissed off an engineering career to bust his knuckles pumping up BMWs. One of  his turbocharged Ultimate Driving Machines first laid a patch on these pages in 1988, and since then, we’ve tested eight Dinan BMWs, more or less melting for them all.


The S3-R M3 is emblematic of the type of audacious tinkering we expect from Dinan Engineering’s workshop in Morgan Hill, California—and the kind of prices. Order everything from Dinan, including the engine, suspension, brakes, wheels, fries and a Coke, and the bill comes to $47,836. That is, after you’ve purchased a $60,575 BMW M3 coupe and $1806 in new tires.

Yes, it’s just a wee bit spendy, but this is no casual slap-on of carbon-fiber flounces and plastic galloons. (Dinan offers at least four variations on this theme, from the highly souped-up S3-R to the cosmetic-only S.) The M3’s stock 4.0-liter V-8—a Valjoux 25-jewel chronograph among car engines—is yanked right out, its major organs eviscerated. This, ahem, voids BMW’s warranty, but Dinan takes over and ensures its work for the same four years or 50,000 miles. Dinan, which also builds BMW’s Daytona Prototype racing engines, then repacks the block with a billet crank, forged pistons, and lighter connecting rods. In the event, the bore widens by two millimeters, to 94, and the stroke lengthens by 7.8 mm, to 83.

Thus, in the $31,234 engine portion of the S3-R makeover, Dinan adds 609 cc of displacement, rechambering the engine into the car as a 4.6-liter. Dinan also bores out the throttle bodies (for greater airflow) and fits a smaller, lightweight crank pulley to lessen parasitic power loss from the water pump, the A/C compressor, and the alternator.

Finally, for this particular car, Dinan bolts on a larger, low-restriction air intake and replaces the exhaust midsection with the company’s own stainless-steel “racing” exhaust (i.e., no catalytic converters), which spits thunderclaps and lightning.

With all the internal changes and external tchotchkes, the power subsequently mushrooms, especially in the middle. The S3-R M3 peaks at 527 horsepower at 7800 rpm, Dinan claims, up 113 and down 500 rpm from stock. Perhaps more significantly, the stock torque figure of 295 pound-feet rises by 112, to 407, though the torque peak also rises, from 3900 rpm to 5200.

With tuner cars, the question always comes down to numbers. Dinan’s power figures are predicated on 93-octane gas, which is nearly unobtainable in 91-only California, where we gave the S3-R M3 its test-track licking. Even so, it should have enough extra power to chisel time off the stock M3’s ETs.

Well, the results proved complicated.

Dinan figured we’d turn a quarter-mile in the low-12-second range, rather than the 12.5 seconds we in fact posted, at 118 mph. The many stock, manual-transmission M3s we’ve tested have been only slightly slower (12.6 to 12.9 seconds).

Doing the pathology on the numbers, we realized that the S3-R M3 cost itself time at the line, spinning its tires. Power is nothing without traction, and the car seems to ride atop its own permanent ice cap. On dusty desert pavement, it easily breaks loose its fat Michelins in first and second gears, so it’s no easy car to get out of the hole.

We were slower to 30 mph than in most other M3s we’ve tested, but then the S3-R M3’s power showed, reeling in the stockers and passing them by 60 mph. The tuned car hit 60 in 4.2 seconds, about two-tenths quicker than most of the stock M3s we’ve tested. A better test surface would certainly make for a better launch, and the Dinan M3 would be quicker at the key marks, no question.

With catalytic converters? Dinan says that would cut 23 horses, but running on 93 octane would add 15, so it shouldn’t make much of a difference

Dinan S2-M3

Dinan S2-M3

Why would anyone acquire a car that already had been thoroughly modified by one of the best performance-car companies in the world and then modify it again? That's the question we asked Steve Dinan, the well-known American tuner, when he came by our sweatshop and dropped off his latest car, a modified BMW M3 he's dubbed the S2-M3.

Simple, says he: "Folks who want to go fast start with the fastest car they can get and then come to me to make it go even faster." For BMW fans, the quickest model is the $48,195 333-hp M3, a legendary car that's always on our 10Best list. It's so good that in 1997 we named it the Best-Handling Car, period—money no object.

It's hard to imagine anyone even trying to improve on the M3, but Dinan says his $17,798 package of engine and suspension mods does indeed do just that. This is not a new experience for us. We had the same doubts last year when he dropped off a reworked M5, but sure enough, we did like it better than the stock car.

Dinan acknowledges the inherent dangers of such ventures and is well aware that in stock trim the M3's 333-hp, 3.2-liter six-cylinder engine, for example, is already highly tuned, and there aren't a lot of inexpensive things he can do to significantly increase horsepower. That's why the list of new power parts has just three items on it: an airbox, an airflow meter, and a muffler.

The airbox is larger than the stock unit and also has a snorkel that inhales cold air from the area between the top of the front grille and the hood. In addition to the less restrictive airflow meter, the package includes the relocation of the intake-air-temperature sensor so it's closer to the six throttle bodies, a move Dinan says provides the engine computer with more accurate intake-air-temperature readings. The throttle bodies are also bored out for further airflow increases.

The only change to the exhaust system is the muffler. The standard M3 uses a muffler that has two outlets, so from the rear of the car there are two pairs of exhaust pipes sticking out. Dinan's muffler uses only one larger, smoother outlet because he says more air is able to flow out. A dummy pair of exhaust tips retains the stock look.

Finally, Dinan reprograms the M3's engine computer, which controls a great many engine functions, including the intake- and exhaust-valve timing, spark timing, fuel flow, and throttles. In addition to adapting those engine parameters to the new parts, Dinan increased the rev limit by 200 rpm to 8200 and also removed the top-speed governor. We don't top-speed-test modified cars, but Dinan says the S2-M3 is good for 189 mph.

All the modifications added a claimed 28 horses to the power bank, an 8.4-percent improvement. That's not enough for a customer to sense a thrilling boost in power, so as part of the package, Dinan also puts in a shorter final-drive ratio (3.91:1 versus 3.62:1) to make for sprightlier sprints. It is also interesting to note that thanks to the higher rev limit Dinan's car clears 60 mph in second gear, the same as the stock car.

Dinan feels the greatest improvement he's made over the stock M3 is in the suspension department. As we do, he thinks the M3 is too stiff, but he goes even further, contending that the handling benefits don't justify that hard ride. So the S2-M3 package includes new 12-position adjustable shocks and anti-roll bars, stiffer springs, front camber plates, front and rear strut-tower braces, and larger wheels and tires. Dinan claims his car rides about as well—or not—as the stocker but has a lot more grip. Its 0.96-g skidpad figure is a bunch more than a stock M3's. We've tested three stockers, and the numbers have ranged from 0.84 to 0.87.

We did not see that much of an improvement during the acceleration tests. The S2-M3 zips to 60 mph in only 4.6 seconds, but we've tested a stocker that hit 60 in 4.5. Similarly, the S2-M3 cleared the quarter in 13.2 seconds at 107 mph, and that quick stocker did it in 13.1 at 107. It's worth noting that we've also tested an M3 that needed 4.8 seconds to reach 60 mph and 13.6 seconds to hit the quarter at 105 mph.

Dinan did, however, improve the handling. There's a crispness in the S2-M3 that adds a wonderful liveliness to the driving experience. It's sort of a strange thing, because if you drive an M3, you think it handles pretty well and there aren't really any faults. But then you drive the Dinan car, and it's as if someone had turned on the lights.

Especially noticeable was the turn-in response. The S2-M3 rips through turns with an easy controllability and seemingly limitless grip. We didn't tinker with the adjustable shocks (ours were set with the front slightly stiffer than the rear), but Dinan says there's a large range of adjustability that allows owners to fine-tune the handling for precisely the balance desired. The Dinan car isn't necessarily faster at the drag strip, but on a racetrack, where the extra grip and handling would come into play, it would leave the stocker for dead.

If you don't have the cash for the entire S2-M3 package, all the parts—which are covered by a warranty that matches BMW's new-car one—are available à la carte at one of the 120 BMW dealers that carry and install Dinan parts.

Dinan ISR 3-BMW M Roadster

Dinan ISR 3-BMW M Roadster

You've probably noticed by now that the latest BMW M3 has arrived here with a more powerful engine that used to be exclusive to the European market. What you might not know is that the new engine will also power the 2001 M roadster and M coupe models. That pretty much renders your older M coupe or roadster obsolete, doesn't it?

Unless, that is, you ordered your car to be modified and supplied by Dinan as a factory-works vehicle -- a program Dinan runs in conjunction with BMW of North America through 76 authorized dealers to supply super-quick variants with fully supported warranties.

In the case of M roadsters and coupes, the breathed-on models are available in three stages of tune. S1 and S2 packages include suspension tweaks, engine software upgrades, and induction and exhaust modifications, along with a Dinan plaque and badging. The Stage 2 kit, predictably, goes further with the upgrades and adds big wheels.

But for the seriously horsepower-hungry owner (no need to raise your hand), there's the Dinan ISR 3. That's shorthand for intercooled, supercharged roadster, 3-series, which provides 396 horsepower at 6500 rpm and a stump-tugging 326 pound-feet of torque at 5500.

Sure, the Dodge Viper does even better than that, but this is a 13-foot-long street luge with a 3.2-liter engine. Having close to 400 horsepower in this car would feel almost indecent if it weren't so much fun. There will be only 50 of these ISR 3s produced, so consider yourself fortunate if you ever get to drive one. And consider yourself extremely well heeled if you buy one, because the premium for this little rocketship is $37,000. Yeah, that's on top of the $43,270 base price of an M roadster, ratcheting your out-of-pocket expenses to a whopping $80,270.

For that you get a belt-driven Vortech supercharger delivering 10 pounds of boost to the engine via an air-to-air intercooler that is fitted in the front of the engine bay, where it shares the wind blast produced by the radiator fan. The fan comes on automatically when the engine senses boost and stays on for three minutes to reduce heat soak.

Two differently sized compressor bypass valves are fitted, one ahead and one aft of the intercooler, to eliminate surging or stumbling. The engine also wears an oil cooler; large-diameter, high-flow throttle-body and airflow-meter assemblies; and a high-flow fuel-delivery system to provide sufficient fuel for the increased airflow. A polished and ported intake manifold with increased runner diameters conducts the high-pressure air to the cylinders, while a free-flow stainless-steel exhaust system eases the gas out to the accompaniment of a fine baritone sound.

Both the engine-control computer and the VANOS variable-valve-timing system were reprogrammed to match the engine's new power characteristics. To get all this newfound grunt to the road, Dinan fitted a lightweight clutch assembly that is nearly 15 pounds lighter than BMW's dual-mass unit yet has a 20-percent-greater clamping force. Then, because the car wears big 285/40ZR-17 tires on the rear axle, Dinan replaced the stock 3.23:1 rear end with a limited-slip 3.38:1 differential.

That took care of the motivating aspects of the ISR 3, in itself not an easy or quick exercise, but Steve Dinan soon found that the stock chassis would not handle the power increases safely without substantial revision. The Z3 family, you might remember, took the semi-trailing-arm rear suspension from earlier BMW models. Dinan found the rear end prone to rapid camber and toe-angle shifts during pitch and roll that produced spooky handling.

Chassis flex added its own weird inputs, so Dinan bolted in a strut-tower brace as well as a set of matched performance springs, specially valved Dinan/Koni shocks, anti-roll bars, and camber-control devices. The result is a car that pulled 0.91 g in our skidpad test (Dinan says he has seen 0.92 g) and drove with a surprising combination of comfort and precision.

The ISR 3 now feels secure and planted in bends, with limited sensitivity to throttle position. Body-motion control, it has to be said, is tight, but the car responds in a more linear fashion than its stock siblings, and even the big 255/40ZR-17 front tires haven't markedly increased the front end's sensitivity to pavement grooves. Continued.