The super heated exhaust gases expelled from the new BMW 335i sedan’s dual pipes whipped past my cheeks, even though I was standing in an outdoor parking lot 15 feet behind it, as a screaming wail emanated from the uncorked twin turbo engine, a wail that bounced off three walls and stopped bystanders outside in their tracks. All in an effort to unravel the mystery of exactly how much power the new-for-2007 four-door actually produces.

Acceleration times and various reports from American publications about the same engine in the 335i Coupe suggested that BMW underrated the 335i’s horsepower and torque numbers significantly, even though both figures officially stand at a very healthy 300 each. With the M3 going away for the 2007 model year, the 335i becomes the most powerful 3-Series now available, and undoubtedly the most powerful 3-Series sedan ever offered in North America.

For 1997 to 1998, BMW offered a four-door version of the 240 hp M3, allowing buyers who needed the practicality of four doors to revel in the M3’s extra power and enhanced handling. Sure, there’s more to life than power, but whether you’re a hard-working business exec, a politician or just a fan of performance-oriented four-wheel motivation, it’s an addictive commodity.

Power exceeds official ratings, well into M3 territory, dyno test shows

Clearly, BMW has subtly tapped the innate appeal of this power and control in its popular 3-Series cars. Since the M3’s debut in 1986, it has been the most powerful, quickest-reacting version of the compact 3-Series, an adrenaline-fueled glass and metal embodiment of BMW’s ultimate driving machine philosophy. But that run is now over, at least until the upcoming V8 M3 is introduced later this year.

BMW 335i

In fall 2006, BMW quietly released the all-new twin turbo engine at the top of its regular 3-Series four-door lineup, which originally debuted in the 2007 335i Coupe only a month earlier to much fanfare. In fact, the 335i’s engine may match the power of the outgoing 333 hp M3 – in reality, if not going by its official figures – and we have the first Canadian dynamometer test results to prove it.

It was a mild winter day near the end of February when I took a Montego blue 2007 335i sedan to Redline Automotive in Scarborough, Ontario, one of the few performance tuning shops with its own DynoJet Research dynamometer – or dyno, as the power addicts call it. Like emissions testing equipment used in various provinces, it uses rollers imbedded in the shop’s floor to test the performance of the strapped-down vehicle. Only instead of measuring emissions levels, it measures exactly how much horsepower and torque is getting to the drive wheels.

BMW 335i

After two raucous runs up to redline in all six gears, the manual-equipped 335i averaged 274 hp, and 276 lb-ft of torque at the rear wheels. From here is where matters get slightly cloudy. Manufacturers all rate horsepower and torque at the crank, which provides a higher figure, not at the wheels, since there’s always some parasitic loss by the time the engine’s oomph gets transferred from the engine, through the transmission, to the driveshaft and then the tires.

The general rule is a 15 to 20 per cent loss is normal. Another published dyno test done on a non-turbo 2007 BMW 330i found an approximate 20 per cent loss at the wheels. So using that 20 per cent loss figure, the engine in this particular 335i actually produced 329 hp, and 331 lb-ft of torque. This horsepower rating is just a couple ticks below the outgoing M3, and absolutely humbles the M3’s 262 torque figure.

The actual dynamometer chart for the BMW 335i sedan

Still, our numbers never reached the lofty levels achieved by dyno run peaks of 300 in each category reported by a couple of American outlets on the 335i Coupe, which would put the actual crank numbers at 360, despite the power-friendly colder temperatures of this test. Judging from all these dyno numbers, it appears the sedan’s engine or exhaust plumbing results in slightly less power getting to the ground than in its coupe sibling, despite the same official power numbers for two and four-door 335i models.

Aboard a 335Ci Coupe with the 6-speed manual gearbox, we performed the 0-100 km/h dash in 5.3 seconds and covered the quarter mile in 13.70 seconds, with a peak of 168.8 km/h at the timing mark. This is six tenths of a second slower than the hyper-performance Audi RS 4 sedan in the 0-100 test (4.74 seconds) and quarter mile (13.07 seconds / 176.3 km/h), a car that costs about double the 335i sedan’s $49,900 base price.

And by comparison, the last BMW M3 we tested (with SMG 6-speed sequential manual gearbox) did the 0-100 km/h dash in 5.59 seconds and covered the quarter mile in 13.86 seconds, with a peak of 165.9 km/h at the mark.

Numbers prove themselves on the road

The BMW 335i sedan strapped to Redline Automotive's DynoJet Research dynamometer

The 335i sedan’s horsepower numbers may align closely to the M3’s, but its personality behind the wheel is leagues more sophisticated, and as highly polished as Howie Mandel’s bald head. When the M3 is baiting you to work that tachometer to its upper reaches, the 335i has a much smoother and more relaxed comportment at all engine speeds.

Part of this is simply a more refined and insulated edge to its exhaust note, especially north of 5000 rpm, although looking at the dyno numbers, there’s not much point in going past 5600 rpm, as both horsepower and torque decline from there to its 7000 rpm redline.

No, most of the credit for the 335i’s driving manners comes from the gushing geyser of torque available just about as soon as the light goes green. Its official 300 lb-ft of torque comes in at 1400 rpm, or about a toe tickle off idle speed.

BMW 335i

Traffic slowing down on the highway? Leave it in fifth gear, and the car’s torque will get it moving smoothly again from as low as 40 km/h, right up to left lane speeds again, with no hiccup in power or shift required. All that low-end grunt, from a considerably smaller and less thirsty twin turbo 3.0-litre inline six, delivers a very credible imitation of big-bore luxury-class V8.

Of course, how much less thirsty depends greatly upon the vehicle with which you’re comparing it – the 335i’s 12.5 L/100km city, and 7.6 on the highway numbers are just slightly better than the fuel economy figures of the new Lexus LS 460 and its 4.6-litre V8, but not as good as entry-luxury competitors such as the Mercedes-Benz C 350.

These fuel economy numbers are for the six-speed manual transmission model, with premium the recommended fuel, although it ran fine on three quarters of a tank of regular, after the third gas station I stopped in only had 87 octane left.

Interior solidly luxurious, could offer more toys

The car’s interior ambiance reflects its sophisticated yet athletic driving comportment. Leather and metallic finishes adorned this particular tester, with a nicely shaped steering wheel that had finger indents that gently guided the driver’s digits to a proper nine and three position. If the steering wheel and updated driver training hasn’t gotten you to abandon the old 10 and 2 o’clock hand position, then the 335i’s handy multi-function steering wheel stereo and hands-free buttons certainly will.

BMW 335i

Like all latest generation (E92) 3-Series BMWs, the 335i greets its driver with a circular start/stop button that requires the key fob to be pushed into the dash before the button will fire up the car.

After having spent a previous week with a fully-loaded Nissan Maxima that cost about 10 grand less than the $58,900 ‘as-tested’ price of this particular 335i, I missed the Maxima’s heated steering wheel function, which is the next great godsend after heated seats. A heated wheel would have been especially nice here because digging out the BMW’s key fob from a pocket or purse usually requires the removal of gloves outside the car, and especially in a cold vehicle, you’ll likely put those gloves back on.

Large straps keep the BMW 335i on Redline Automotive's DynoJet Research dynamometer

This as tested price did include welcome options such as sports seats with electrically adjustable seat width, a compass mirror, a Harman / Kardon high-end sound system and active steering, which really sharpens the 3’s already quick steering responses.

This tester also included a sport suspension that normally comes with 18-inch wheels, but ours was equipped with Blizzak winter tires and different rims (not included in this as tested price). Both likely contributed to the firm but not pounding reactions to bumps that struck a fine balance with the tight set it took over the few challenging dry corners I enjoyed in my time with it.

The rear seat may be bigger than that in the previous-generation 3-Series, but it’s still cozy, with pointy rear doors that make entry and exit slightly more cumbersome than most, especially in tight shopping malls.

Conclusion

It’s hard not to love the 335i sedan: it offers the practicality of four doors, sports car worthy power, and a sparklingly debonair driving experience. North Americans have waited a long time to see a turbocharged BMW on these shores, and this jewel of an engine was certainly worth the wait.

ROAD TEST SUMMARY

BMW 335i

Here are the salient points and overall rating of this new model, as established by our reviewer:

Overall rating: 9.0 / 10

Pros

  • Most powerful 3-Series sedan ever offered in North America (including 4-door M3s)
  • Lovely twin turbo engine with manners and muscle like a luxury-class V8
  • Looks so much like a mild-mannered 3-Series
  • An all-wheel drive version is coming in the summer

Cons

  • Not the most inexpensive vehicle in its class
  • Tight rear seat and no wagon version hurt practicality quotient
  • Needs premium fuel for high performance
  • Looks so much like a mild-mannered 3-Series