BMW 3-Series Coupe
BMW announced substantial enhancements to the 2011 3 Series Coupe, including outstanding style updates for 328i and 335i models and a new engine for 335i models. The 2011 3 Series Coupe models went on sale in Spring 2010. The 328i Coupe and 335i Coupe start at $37,575 and $44,025, respectively, including $875 Destination & Handling. The all-wheel drive models 328i xDrive Coupe and 335i xDrive Coupe start at $39,475 and $45,925 respectively.
Fundamentally unchanged are each car’s essential attributes of rear-wheel drive, near-perfect 50-50 weight distribution, remarkably precise steering, and skillfully engineered suspension…all of which conspire to produce the uniquely satisfying driving experience that is quintessentially BMW.
All-new is the engine for the 335i model. Internally designated the “N55,” this turbocharged, all-aluminum engine features essentially the same “short block” and 3.0-liter displacement of its predecessor, but benefits from five additional years worth of development and refinement. The result is an engine that is more responsive, more fuel efficient, and cleaner-running than its outstanding predecessor, but preserves the previous engine’s output and soul: 300 horsepower and 300 lb-ft of torque, and a 7,000 rpm redline. The 6-speed manual gearbox – beloved by North American enthusiast drivers - remains standard, and the well-known 6-speed Steptronic automatic is optional, now featuring “pull-style” shift paddles on the multifunction steering wheel.
The 2011 BMW 335i xDrive Coupe combines all-wheel drive with the power of BMW’s famed 300-horsepower, turbocharged 3.0-liter six-cylinder engine. Likewise, the 2011 BMW 328i xDrive Coupe continues to impress with its 230-hp, naturally-aspirated 3.0-liter six-cylinder engine featuring magnesium-aluminum construction. On smooth, dry roads BMW’s xDrive gives a sporty, rear-wheel drive feel. But hit a wet or snow-covered road, and xDrive automatically sends more torque to the axle with more traction.
Fundamentally unchanged – and still not successfully challenged in other quarters – are the Coupes’ essential attributes of rear-(or all-)wheel drive, harmonious front/rear weight balance, outstandingly precise steering and skillfully engineered suspension…all of which conspire to produce the uniquely satisfying driving experience that is quintessentially BMW.
BMW’s xDrive is the most sophisticated and responsive all-wheel drive system on the market today. It has proven its merits, in terms of agility and safety, in the 19 BMW models currently offered with xDrive in the U.S.
In addition to the standard six-speed manual transmission, the BMW 3 Series Coupes are available with a six-speed Steptronic automatic transmission. Designed for responsiveness, this innovation enhances driving dynamics without sacrificing fuel efficiency.
The distinctive character of the BMW 3 Series Coupes is instantly recognizable from the very first glance. Over and above the basic shape of the car and its classic lines, the design of the headlights, the detail of the taillights, the interior and even the exterior mirrors were specifically created for the Coupes. These unique design elements reflect the special character of this elegant and sporty car. The driver who chooses a coupe wants a car with elegant looks as well as driving dynamics. With this in mind, BMW engineers and designers set out to create a unique yet unmistakable blend of design, features and most importantly, driving pleasure.
BMW 3 Series Coupe customers have a choice of two inline-6 engines that are the worlds’ finest. The 328i features 230 horsepower while the 335i has 300 horsepower and is the first inline-6 equipped with a single twin-scroll turbocharger, BMW’s Valvetronic throttle-less intake technology, High Precision direct fuel injection, and all-aluminum construction.
The 335i’s new inline-6 engine displaces 3.0-liters and develops maximum output of 300 hp at 5,800 rpm, with peak torque of 300 lb-ft available all the way from 1,200–5,000 rpm. Redline is 7,000 rpm. This is the same level of performance as the previous 3.0-liter twin-turbo inline-6 but with the innovation of twin-scroll technology and the integration of Valvetronic, this new engine is even more fuel efficient.
Historically, BMW engineers were never satisfied with the most often-cited downside to turbocharging: the frustrating “turbo lag” that occurs between the times at which driver presses the accelerator pedal and when the turbocharger develops sufficient rotation to increase power. Turbo lag is usually worse at low engine speeds. Other drawbacks included relatively high fuel consumption and poor emissions output. At the time, turbocharger technology was not a reliable, practical or efficient was to make power. For these and other reasons, BMW put turbocharged gasoline engines on the shelf for more than 20 years.
Two recent developments caused BMW to reconsider turbocharging. While many luxury-performance carmakers began to achieve power gains by building engines of ever-increasing displacement, BMW looked for a more efficient way; smaller engines and turbocharging made sense. Also, the technology transfer from BMW’s turbocharged diesel engines could easily be transferred to their gasoline-fired counterparts. Accordingly, BMW articulated its new approach to developing high-performance engines as part of its EfficientDynamics initiative.
The new N55 is the first BMW inline-6 to combine turbocharging, High Precision direct fuel injection, and Valvetronic variable intake technology. It features a single, mid-sized turbocharger with a “twin-scroll” housing to boost performance and minimize the response lag. Thanks to its housing design which maintains proper separation between streams of exhaust gasses, the turbocharger builds up pressure much faster than previous-generation turbochargers, thus eliminating even the slightest tendency for lag.
A further advantage of turbocharging is that this is the most weight-efficient method to boost engine power and performance. The N55 turbocharged inline-6 weighs approximately 150 lbs. less than an equally powerful eight-cylinder engine displacing 4.0 liters. This lower weight means a significant advantage not only in fuel economy, but also in balancing the car's weight distribution.
Using Valvetronic for the first time on a turbocharged inline-6 allows the engine to “inhale” air for combustion with virtually no delay and with reduced pumping losses. As a result, the engine makes power more quickly than ever before, and this is proven by the N55’s ability to reach peak torque at 1200rpm, 200rpm earlier than its predecessor.
As a result, the technology in the BMW 335i Coupe represents a significant achievement in terms of both performance and fuel efficiency. The advantages over a conventional turbocharged engine are not only clearly measurable, but easy to feel on the road.
Turbocharging typically includes intercooling of the engine's induction air, that is, cooling the compressed air that emerges, very much heated up by the compression process, from the turbocharger(s). Sometimes it's done with coolant; in the case of the N55 engine, it's accomplished with outside air. Intercooling is necessary to reduce the temperature of the incoming air to preclude detonation or "knocking" that can reduce power or, in the extreme, damage the engine. Of course, the N55, like all other current BMW engines, is equipped with knock control as part of the Digital Motor Electronics (DME) engine management system. On the N55 engine, the DME is now mounted directly to the top of the engine for better packaging and weight savings.
The significant loads and cylinder pressures of the N55 300-hp engine required the use of an aluminum engine structure with cast-iron cylinder sleeves. Altogether, the N55 weighs about 427 lbs. The 335i Coupe dual exhaust system runs at both sides of the vehicle. At low loads, a flap channels most gas through one side to reduce low-frequency exhaust "rumble." The 335i Coupe features an air-to-oil external oil cooler mounted in one wheel well as opposed to the N52's coolant-to-oil unit.
The peak power of 300 hp at 5800rpm has already been mentioned. At least as important is the fact that this engine can deliver its peak torque from 1200 rpm - not far above idling - to 5000 rpm. On the road, this power and torque result in outstanding performance. The 335i Coupe can accelerate from 0 - 60 mph in just 5.3 (5.5) seconds when equipped with the manual (automatic) transmission. The sense of urgency continues all the way to the electronically limited top speed of 130 mph (150 mph when equipped with the optional Sport Package). The 335i xDrive Coupe accelerates 0-60 mph in 5.2 (5.3) seconds when equipped with the manual (automatic) transmission.
Finally, the new N55 engine is able to achieve a more favorable emissions signature than its predecessor. The single turbocharger has only one exhaust path and feeds a single catalytic converter in place of the previous engine’s two. This means the exhaust gases are concentrated at the catalytic converter for better cold-start emissions performance, making the N55 a more environmentally friendly engine.
The 328i Coupe is powered by BMW's 230 horsepower, 200 lb-ft, 3.0-liter inline-6 engine, known internally as the N52. Its magnesium/aluminum construction and Valvetronic variable valve lift are features found only on BMW engines. The N52 achieves impressive progress on all performance and technology fronts, especially in its remarkably light weight of 357 lbs. An aluminum/magnesium engine block, hollow camshafts, plastic camshaft cover, improved combustion chambers, a further evolved Double VANOS , higher fuel injection pressure, sophisticated engine electronics, an electric coolant pump, a variable-volume oil pump and an oil/coolant heat exchanger are the other weight-saving features and improvements of this engine over previous generations.
Source: BMW press