2009 3 Series refresh details Part 2

Details from BMW on the 2009 3 Series mid-life refresh, continued.

BMW PR
July 2008

Section 8: The intelligent all-wheel drive system BMW xDrive: Variable, dynamic, supreme - now also in the BMW 320d xDrive.

[floatleft] View attachment 657 [/floatleft]• BMW as the world's most successful provider of all-wheel drive vehicles in the premium segment.
• Intelligent all-wheel drive system BMW xDrive even more precise due to controlled brake intervention with torque compensation.
• BMW xDrive now available for five engine types - new: BMW 320d xDrive.

BMW has established itself worldwide as the market leader for all-wheel drive vehicles in the premium segment. No other all-wheel drive system enhances driving dynamics, traction and stability like BMW xDrive. The outstanding quality of the electronically controlled and variable power distribution between front and rear wheels is impressively brought to bear in the vehicles fitted with BMW xDrive both on difficult terrain and on surfaced roads.

The first BMW all-wheel model went on the market in 1985: a BMW 325iX. Since then BMW xDrive has continuously increased in importance in the model range of the BMW 3 Series. The all-wheel drive system is available for the Saloon and Touring models as well as the BMW 3 Series Coupé. For the first time, the new BMW 3 Series now also offers the option of a 4-cylinder model fitted with the intelligent all-wheel drive system. The new BMW 320d xDrive combines outstanding efficiency with superior driving dynamics and traction qualities.

For the Saloon, Touring and Coupé models of the BMW 3 Series there are three petrol engines and two diesel engines available in combination with BMW xDrive. The models in question now bear the designations BMW 335i xDrive, BMW 330i xDrive, BMW 325i xDrive, BMW 330d xDrive and BMW 320d xDrive.

BMW xDrive: variable, precise power distribution and fast response in every situation on the road.

The electronically controlled, permanent all-wheel drive system BMW xDrive offers an incomparable degree of comfort, traction and agility over all road surfaces with its situation-based distribution of drive torque between the front and rear axles. BMW xDrive acquires its status as an intelligent all-wheel drive system from the fact that it always directs drive power to the axle whose wheels have the best contact with the road surface, by means of a transfer gearbox with an electronically controlled multi-plate clutch which operates precisely according to the prevailing situation. The system responds with outstanding accuracy and speed to any change in the driving situation.

In normal driving situations, BMW xDrive distributes drive torque to the front and rear axle at a ratio of 40:60. Here, sensors constantly measure slip at the wheels of the front and rear axle. Within a fraction of a second, the system is able to vary the ratio of power distribution. Unlike conventional all-wheel drive systems, BMW xDrive also responds in anticipation, not waiting until a wheel actually starts to spin. The vehicle is thus stabilised before the driver registers any need for action.

For even more precise control, the computer units of the driving stability regulation system Dynamic Stability Control (DSC) and the xDrive are networked with one another in the Integrated Chassis Management (ICM). This high-performance electronic control system enables the drive and chassis functions to harmonise within a fraction of a second so that maximum stability and performance are available in every situation on the road. Even in the event of sudden changes in conditions - such as changes in the road surface, spontaneous steering manoeuvres, abrupt acceleration or braking - the ICM responds precisely by activating the DSC and xDrive actuators, optionally also those of the Active Steering. The type and extent of such interventions is always such that not only driving stability but also dynamic performance are maintained at the highest possible level.

Optimised supremacy due to measured brake intervention with torque compensation - an evolution of DSC.

With these capabilities, xDrive enhances driving dynamics because it detects any tendency to oversteer or understeer early on and counteracts effectively. The close interaction between DSC and xDrive via ICM also enables carefully measured brake intervention with torque compensation: this effectively anticipates any tendency to understeer on slippery surfaces or when taking a corner at speed. As soon as the front wheels push excessively towards the outside, the inside rear wheel is selectively braked via the DSC control function. The loss of propulsion thus brought about is compensated for by an increase in drive power so that corners can be taken more precisely even on slippery surfaces.

Section 9: The history: From pioneer to role model for dynamic performance in the medium category.

• 1975: premiere for a new vehicle category.
• Ongoing progress: the BMW 3 Series as a bearer of innovation.
• Setting the benchmark in the segment over five model generations.

[floatleft] View attachment 659 [/floatleft]To be exact, the history of the BMW 3 Series began in March 1966 - with the presentation of the BMW 1600-2 at the Geneva Salon. This was the starting signal for what was then the smallest BMW model series: a 2-door Saloon with a sports-style design and an engine with a slightly coupé-like character as well as the classic engineering features of the engine at the front and rear- wheel drive. The BMW 3 Series has always remained faithful to this fundamental principle and acquired its new designation at its premiere in 1975 as a new vehicle category within the BMW model architecture.

Over five model generations, the BMW 3 Series has always remained faithful to its character as an agile, smart automobile with an engine of excellent quality - and indeed went on to become the original role model for this type of vehicle. But it has also repeatedly been a pioneer of technological progress and has set the benchmark in its segment.

The first generation: the 3 Series BMW instantly becomes an original.

While the first generation of the BMW 3 Series (1975 to 1983) had a single body shape and initially four - later five - engine types with up to 143 bhp in the BMW 323i, the number of versions and engine types was to multiply significantly over the next 30 years.

The second generation: variety of versions.

The second generation (1982 to 1994) brought with it a second body version with the first four-door model, a third body version with the Convertible and a fourth with the Touring (at the time deliberately spelt in lowercase letters), as well as the first all-wheel drive version. In addition to powerful 4-cylinder and 6-cylinder petrol engines with up to 171 bhp, an 86 bhp diesel engine was also offered for the first time. As a high-performance version, BMW Motor- sport GmbH contributed the M3 - initially with 200 bhp, later 238 bhp.

The third generation: the advance in design.

The third generation (1990 to 2000) started out with a completely new styling, the body also increasing notably in size to allow for a more comfortable and safer passenger cell. In the engine area the use of 4-valve technology brought about a significant increase in output: the range now went from 100 bhp in the BMW 316i to 193 bhp in the BMW 328i Coupé. As a fifth body version alongside the Saloon, Coupé, Touring and Convertible the BMW 3 Series compact was now introduced which for the first time offered an 87 bhp engine running on CNG gas in addition to petrol and diesel versions.

The fourth generation: a firework display of innovations.

In May 1998 the fourth BMW 3 Series was launched - initially as a 4-door Saloon once again, with increased comfort, safety and performance. And it did so with a bang: the BMW 320d was the first BMW with a direct injection engine, overshadowing everything else in its category with an output of 100 kW/136 bhp, a top speed of 207 km/h and a fuel consumption of 5.7 litres.

The other engine versions were equally groundbreaking: the basic model was the BMW 318i with 118 bhp, followed by the BMW 320i with 150 bhp and six cylinders, the BMW 323i with 170 bhp and finally the BMW 328 with 193 bhp. And these engines had many new features to offer: inside the 1.8-litre 4-cylinder engine there were two balancing shafts which improved the noise level inside the car by up to 10 dBA as compared to the predecessor model. The technologically most prominent measure in the 6-cylinder engines was the introduction of Double Vanos to provide a fuller torque curve and further reduce the level of pollutants in the exhaust gas.

With the combination of rear-wheel drive, an ideal weight distribution of 50:50, the electronic regulation systems ABS, ASC+T and the dynamic stability control system DSC III, the chassis of the BMW 3 Series moved the bench-mark up to a new level. A highlight in this package was the ITS head airbag, a tube-like structure hidden in the door frame next to the driver and front passenger ensuring significantly improved head protection over previous systems.

But it was not only these spectacular new features which allowed the 3 Series to advance into regions otherwise reserved for the luxury performance segment. BMW also introduced the new Car Memory and Key Memory as standard features, as well as offering the multifunction steering wheel, rain sensor and Steptronic as optional extras. From autumn 1998 there followed integrated children's seats, RDC, xenon light, on-board monitor with navigation system, TV and extended on-board computer.

In addition to the Saloon, the highlights in the model range of the fourth gene-ration were the new versions of the Coupé, Touring, Convertible and compact, with the BMW 330d as a special highlight. With a rated torque of 390 Nm from 1,750 rpm, the 6-cylinder diesel was a sheer power package with extreme running smoothness. The enormous pulling power was also reflected in the vehicle's impressive elasticity. The car's average fuel consumption of 7.0 litres diesel to 100 kilometres with a rated output of 135 kW/184 bhp and a maxi-mum speed of 225 km/h gave a whole new dimension to the idea of efficiency. The technological concept of the DI 6-cylinder engine was largely that of the 4-cylinder, with 4-valve technology, VNT turbocharger and charge-air cooling, though there was one crucial difference: instead of a distributor injection pump, a common rail system performed the function of supplying fuel to the cylinders.

One of the last new models of this fourth generation of the BMW 3 Series was by no means a latecomer but a pioneer. In the BMW 330Cd, BMW offered a diesel engine in a Coupé for the first time. The 204 bhp power package - by that time the DI 6-cylinder had been given a power boost - drove just as one would expect of a BMW Coupé but was still a diesel with all the associated benefits: 410 Nm of torque at 1,500 rpm and an average fuel consumption of 6.6 litres.

The fifth generation: BMW EfficientDynamics and much more besides.

The fifth generation of the BMW 3 Series celebrated its world premiere at the Geneva International Automobile Salon in 2005. As usual, the Saloon model was launched first. Its striking appearance with short body overhangs, dynamic lines and a progressive shaping style instantly gave it a distinctive character.

A stir was caused by the new in-line 6-cylinder, the first engine in the world to be fitted with a magnesium-aluminium compound crankcase. In addition, the variable valve control system Valvetronic was applied to the 6-cylinder engine for the first time. In combination with the variable camshaft control Double Vanos, this led to an even more spontaneous and more efficient fuel supply. The new BMW 330i delivered 190 kW/258 bhp from a capacity of 3.0 litres and generated a maximum torque of 300 Nm. 6.3 seconds were sufficient for the spurt to 100 km/h, while its average fuel consumption was 8.7 litres per 100 kilometres. The two 4-cylinder engines each had a capacity of 2.0 litres: the diesel engine in the BMW 320d delivered 120 kW/163 bhp, the petrol engine in the BMW 320i managed 110 kW/150 bhp.

The engineers had completely redeveloped the chassis of the BMW 3 Series. Its double joint spring strut front suspension was made entirely of aluminium, the five-link rear axle was a lightweight steel construction. The driving stability regulation function DSC was fitted as standard with the addition of functions such as brake readiness and hill start assist. The BMW 3 Series was also the first vehicle in its segment to be fitted with Active Steering. Another new feature: Active Cruise Control with radar distance sensor which automatically maintained a specified distance to the vehicle in front, if necessary applying the brakes to do so. The groundbreaking operating concept BMW iDrive was also introduced to the BMW 3 Series.

In September 2006 the new BMW 3 Series Coupé surprised the world with yet another sensation: for the first time since the 1970s there was once again a petrol engine under the bonnet with turbo technology. The 225 kW/306 bhp 3-litre engine saw its world premiere as the first in-line 6-cylinder with Twin Turbo charging, petrol direct injection (High Precision Injection) and an all-aluminium crankcase in the BMW 335i Coupé. Powered by the high-performance engine with the world's first large-scale serial production jet-guided petrol-direct injection system, the top model achieved a fascinating acceleration rate of just 5.5 seconds from zero to 100 km/h. With its average fuel consumption of 9.5 litres per 100 kilometres in line with the EU norm it also set standards within the competitive environment.

For the first time, the BMW 3 Series Coupé was also offered with the intelligent all-wheel drive system xDrive. As an alternative to standard drive the all-wheel drive system provided further improvement in traction and drive stability over slippery surfaces. The positive effects of xDrive in terms of driving dynamics were also immediately appreciated in the BMW 3 Series Coupé.

Since March 2007 the first BMW Convertible with retractable hard top has unleashed a new open-top euphoria. And the models powered by diesel engines are growing in popularity, too. All in all, the Convertible offers a degree of comfort, solidity and value which is unique in the segment. The triple-section roof in lightweight steel panel construction spreads itself fully automatically and within just 23 seconds across the passenger compartment. It is stored at the rear of the open-top two-door model slightly more quickly - in exactly 22 seconds.

At the same time as the launch of the new BMW 3 Series Convertible, a whole new generation of 6-cylinder engines was presented, along with the first BMW 4-cylinder engine with petrol direct injection. The new engines with High Precision Injection in lean operation mode are now available in all versions of the BMW 3 Series. As compared to predecessor engines, they provide significantly improved driving performance figures in combination with a noticeable reduction in fuel consumption and exhaust emission levels - in line with the development strategy BMW EfficientDynamics.

Once again, as so often in the course of the 30-year history of the BMW 3 Series, it has done justice to its reputation as the true original of its category and a pioneer of technology.

Section 10: The new sports automatic transmission with double clutch in the BMW 3 Series Coupé and the BMW 3 Series Convertible: Constant pulling power for maximum dynamic performance.

• New 7-speed sports automatic transmission with double clutch, shifts without any interruption of traction.
• Increase in sprint capacity, reduced fuel consumption and exhaust emissions.
• Premiere in the BMW 335i Coupé and BMW 335i Convertible.

[floatleft] View attachment 658
BMW DCT gearbox.
[/floatleft]BMW presents a enthralling alternative to the 6-speed manual transmission which fascinates drivers with sporty ambitions while at the same time providing all the convenience of an automatic transmission. The new 7-speed sports automatic transmission with double clutch (DKG) now available in the BMW 3 Series enables even more dynamic acceleration and contributes to the reduction of fuel consumption and exhaust emission levels: with these properties it represents the sportiest embodiment of the development strategy BMW EfficientDynamics. The new sports automatic transmission gives the driver the choice between automated shifting and manual gear selection. In both cases, the 7-speed double clutch transmission shifts without interruption of traction, thus enhancing both sporty drive response and shift comfort. The result is a unique combination of further increased dynamic performance when shifting manually with the comfort provided by automatic transmission - and at fuel consumption and exhaust emission levels which are even lower than those of manual transmission vehicles.

A newly designed shift lever is provided in the central console to operate the system. It is clearly differentiated from a conventional automatic transmission selector lever in its shape and its integrated display for the selected shift program; what is more it does not relay commands for the shift program selec-tion or gear change by means of a mechanical connection but electronically. Alternatively, the driver can carry out manual gearshifts using so-called shift paddles which are attached to the steering wheel. The power transmission system developed for the BMW 3 Series is designed for especially powerful and high-revving engines in vehicles with rear-wheel drive. Consequently its debut is in the models BMW 335i Coupé and BMW 335i Convertible, where it is featured in combination with the 225 kW/306 bhp in-line 6-cylinder engine with Twin Turbo and High Precision Injection.

Sports automatic transmission with double clutch in the BMW 3 Series: faster but more economical, too.

The gradation of the 7-speed transmission ensures a constant increase in speed which is continued at an optimum follow-up engine speed after each shift. No time is lost while changing gear because there is no interruption of traction.

The sports automatic transmission completes entire gearshifts within a period of time which in manual transmission vehicles would at most be suffi-cient to open the clutch. The result: outstanding acceleration rates. The BMW 335i Coupé with sports automatic transmission completes the sprint from zero to 100 km/h in just 5.4 seconds - 0.1 seconds faster than the model fitted as standard with 6-speed manual transmission (5.5 seconds) and 0.3 seconds faster than the BMW 335i Coupé with the previously available 6-speed automatic transmission.

The benefits of shifting without interruption of traction and the small steps in engine speed are not only reflected in driving dynamics but also in ride comfort and efficiency. Excellent acceleration goes hand in hand with outstanding shift comfort in urban traffic. The swift, jerk-free change of gears makes for exceptionally harmonious acceleration manoeuvres. The unavoidable load change reactions associated with conventional transmission systems are completely eliminated: even when driving with maximum dynamic performance, a level of ride comfort is achieved which was not previously feasible.

Due to the swift and precise selection of the ideal gear, the efficiency of the vehicle is further optimised. The BMW 335i Coupé with sports automatic transmission achieves an average fuel consumption in the EU test cycle of 8.8 litres per 100 kilometres. The average fuel consumption of the BMW 335i Convertible with sports automatic transmission is 9.1 litres per 100 kilometres. This is equivalent to a reduction in fuel consumption of up to five per cent as compared to the equivalent models with 6-speed manual transmission and with 6-speed automatic transmission.
Three operating modes, new gear lever, manual gearshift using paddles at the steering wheel.

The newly design shift lever for the sports automatic transmission with double clutch serves both to change between shift modes and to relay shift commands for manual gear selection. Its shift layout is the same as that of a regular automatic transmission, though the lever always returns to its original position after activation. The sports automatic transmission with double clutch is not operated mechanically but by means of electrical signals. The current shift program or gear position is shown in the display panel of the shift lever and in the instrument panel.

The new sports automatic transmission with double clutch ensures faster and more comfortable gear changes in three operating modes. Automated gearshifts are made both in the comfort-oriented D mode and in the sporty-oriented S mode. The S mode is activated by shifting the lever to the left. An additional shift of the selector lever to the front (-) or rear (+) activates the manual shift mode. The driver can opt for manual gearshift at any time, both in the D mode and the S mode. The driver simply makes the first shift using the paddles at the steering wheel. The instrument panel then shows an M symbol in conjunction with the relevant gear, instead of the S symbol.

Maximum dynamic performance: sports button and Launch Control.

When accelerating in automated shift mode, the gear shifts S mode are undertaken significantly later in S mode than in D mode so as to exploit engine torque more fully. In addition, the shift characteristics of the sports automatic transmission with double clutch can be influenced by using the sports button in the central console. By pressing this button, both the accelerator pedal and the gear shift response are given a sportier profile. This creates a perceptibly power-oriented acceleration response with faster gearshifts, both in the D and the S mode of the sports automatic transmission. Gearshifts are effected by means of faster closing of the clutch with sporty feedback to the driver. The combination of S mode and activated sports button thus results in gear-shifts at much higher engine speeds and a highly sporty shift response.

The double clutch transmission is also in contact with the engine manage-ment system when it comes to downshifts. Clutch engagement is very gentle so as to prevent any unwanted braking of the rear wheels. If the transmission electronic system detects a very large jump in engine speed at a change of gear - for example in the case of an extremely sporty driving style and sudden application of the brakes - torque relay to the next gear is delayed until the engine speed regulator has increased engine speed accordingly. This intermediate throttle application further enhances drive stability as well as intensifying the driving experience.

In manual mode the sports automatic transmission with double clutch also provides a Launch Control which enables a standing start with maximum acceleration, adapted to the prevailing conditions in terms of tyre state, road surface and load. The requirement for the use of Launch Control is activation of Dynamic Traction Control (DTC), which raises the threshold response of the Dynamic Stability Control (DSC) function, and of the sports button. Before setting off, the driver must select first gear in manual mode. After releasing the brake pedal and with maximum pressure on the accelerator pedal (kick-down) the vehicle then accelerates in optimum fashion at full throttle with rear wheel slip regulated by DSC - up to maximum speed if desired. Here the double clutch transmission automatically sets the shift points without intervention by the driver so that the optimum follow-up engine speed is always available when shifting up. Once the acceleration manoeuvre is complete, the driver takes control of the gears once more.

Functional principle adapted from motor racing.

The principle of the double clutch transmission has its roots in motor racing. It has become well established on the race track, where even a tenth of a second can decide victory or defeat, as with sequential shifting familiar from Formula 1. Shifting up at full throttle without interruption of traction even makes a professional driver a few valuable fractions of a second faster. For serial production vehicles, the appropriate shift comfort was only possible in combination with engines offering a significantly lower level of output and torque. For the first time it is now possible to make the benefits of the double clutch transmission available at high levels of output and in combination with rear-wheel drive and engines with increased engine speeds. The sports automatic transmission with double clutch is designed for engine speeds of up to 9,000 rpm and torque levels of up to 600 Nm and is therefore ideally suited to the character of the high-revving in-line 6-cylinder engines of BMW.

The sports automatic transmission with double clutch combines two partial gearboxes in one casing, whose compact dimensions are the same as those of a conventional manual transmission. The technical core of the system is provided by two oil-cooled wet clutches. One of the two clutches is for the even transmission stages (2, 4, 6), the other is for the uneven transmission stages (1, 3, 5, 7) and the reverse gear. While the vehicle is moving, one of the two clutches is closed and the other open. During an acceleration manoeuvre - also when shifting down - they thus operate in alternation.

At every gearshift, the opening of the first clutch happens simultaneously with the closing of the second. The transmission control system identifies the next gear with a transmission ratio which is ideally suited to the relevant engine speed and road speed, selecting it in advance and holding it in readiness. For example, if the vehicle is accelerating in third gear the power transmission is effected through the relevant clutch and partial gearbox with the uneven gears. In the partial gearbox responsible for the even transmission stages, the gear required to continue the acceleration process - in this case the fourth

gear - is already engaged. It is then sufficient for the clutch responsible for the fourth gear to close while the clutch for the third gear simultaneously opens: within milliseconds the engine power is transferred to the wheels at the new gear transmission ratio. This enables a jerk-free, comfortable gearshift which is also incomparably fast and without any interruption of traction whatsoever.

The electronic control system detects the driver's wishes.

When selecting the next gear ahead of time, the electronic control system always takes account of the current situation on the road. Based on the accelerator pedal position, the engine speed, road speed and shift program selected, the system identifies the level of intensity of an acceleration manoeuvre as desired by the driver or any intended reduction of speed, for example. The transmission control always provides for as harmonious a continuation of the manoeuvre initiated by the driver as possible. Even in the event of an extremely abrupt change of driving style, any required change of gear is effected with high speed and precision. If for example an initiated acceleration manoeuvre has to be interrupted unexpectedly, the sports automatic transmission with double clutch instantly provides a transmission ratio which is appropriate to the new situation.

Safety and comfort functions supplement sporty character.

The sports automatic transmission with double clutch not only supports the driver in terms of a sporty driving style, it also offers a wide range of safety and comfort functions. The automatic engine speed increase causes a regulation of engine drag torque appropriate to the situation at hand when shifting down at critical moments, thereby preventing the rear of the vehicle from swerving.

For especially slow vehicle movements - for example parking manoeuvres or in stop-and-go traffic - the new sports automatic transmission with double clutch also has a crawl function as familiar from conventional automatic transmissions. Setting off gently without activating the accelerator is thus possible at a maximum level of comfort and regardless of the operating state of the trans-mission. What is more, hill detection ensures that shift timing is oriented towards the route profile. On uphill and downhill slopes, gearshifts are set differently to when driving on the level roads.

In combination with top-of-the-range engine of the BMW 3 Series, the sports automatic transmission with double clutch offers an experience of driving dynamics which was previously only provided by high-performance sports cars.