Press Release
Drivetrain: Top Performer in Power and Efficiency.
Featuring an engine range from 130 kW/177 hp all the way to 225 kW/306 hp, the BMW 1 Series Coupé sets new standards in its segment. All of the power units in the series – both the six-cylinder gasoline engine and the two four-cylinders turbodiesels – offer a particularly impressive combination of dynamic performance, motoring efficiency and running refinement, with superior output on a further improvement of fuel economy and reduced exhaust emissions.
The drive units available for the BMW 1 Series Coupé represent the latest state-of-the-art in BMW engine development and come with all the techno-logies introduced as part of BMW’s EfficientDynamics development strategy for the purpose of minimising fuel consumption and exhaust emissions. The innovations now also featured as standard on the BMW 1 Series Coupé and combined with one another appropriately for each model include Brake Energy Regeneration, Auto Start Stop, a gearshift point indicator, on-demand management of ancillary units, and active improvements in aerodynamics.
These cutting-edge technologies serve to further enhance the already outstanding potential of the newly developed engines in terms of both economy and emission management. So when it comes to acceleration, fuel consumption and CO2 emissions, all variants of the BMW 1 Series Coupé rank right at the top in their respective performance and market segments.
Twin Turbo and High Precision Injection in the BMW 135i Coupé.
225 kW/306 hp from 2,979 cc – figures of this kind clearly characterise the BMW 135i Coupé as the top model in the series. Indeed, the world’s first straight-six power unit with Twin Turbo technology, second-generation direct gasoline injection (High Precision Injection) and an all-aluminium crankcase is the most powerful six-cylinder within the BMW range.
Proudly featured in the BMW 1 Series Coupé, this power unit, already the winner in two categories and in the overall rating of the international Engine of the Year Award, offers a standard of driving pleasure never seen before in the compact car segment.
The BMW 135i Coupé accelerates to 100 km/h in 5.3 seconds and has a top speed limited electronically to 250 km/h or 155 mph. Maximum torque of 400 Newton-metres/295 lb-ft comes within the very broad speed range from 1,300–5,000 rpm, clearly confirming the supreme torque and pulling force of the 3.0-litre. Moderate average fuel consumption in this performance category of just 9.2 litres/100 kilometres (equal to 30.7 mpg imp) in the EU test cycle likewise confirms the qualities of this engine as a particularly fascinating example of BMW EfficientDynamics.
This fascinating power and performance is guaranteed above all by Twin Turbo technology, the combination of two turbochargers each pumping compressed air to three cylinders at a time and thus providing a standard of spontaneity quite unique for a turbocharged power unit. The main advantage of the relatively small turbines is their low inertia when accelerating, elimina-ting the “turbo gap” so typical of conventional turbocharged power units, that is the “waiting period” which usually elapses until the turbocharger develops its boost and extra power.
Benefiting from this technology, the turbocharged power unit in the BMW 135i Coupé develops the same kind of torque and muscle as a far larger normal-aspiration power unit, while avoiding the inevitable increase in weight of such a larger engine with its adverse effects on the balance of
the car.
The introduction of Twin Turbo technology, in combination with High Precision Injection, is therefore a particularly efficient method to offer an even higher standard of power and torque without increasing the weight of the engine.
High Precision Injection plays a key role in reducing the amount of fuel consumed. This second generation of direct gasoline injection enables the Twin Turbo power unit of the new BMW 135i Coupé to provide its extra power without a significant increase in fuel consumption and, at the same time, without making any concessions in terms of driving dynamics.
Positioned within the cylinder head directly next to the spark plugs, the injectors allow unparalleled precision in dosing the amount of fuel injected. Compared with an equally powerful turbocharged engine using conventional gasoline injection into the intake manifold, the power unit featured in
the new BMW 135i Coupé thus offers a significant advantage in fuel economy. And adding the effect of further technologies for greater efficiency such as Brake Energy Regeneration, this creates a balance of driving dynamics and economy quite unique not only in this segment of the market.
Turbodiesel power units featuring a particulates filter as standard.
The turbodiesel power units in the new BMW 1 Series Coupé also enter new dimensions in terms of performance and fuel economy. The first point is that the engines in the BMW 123d Coupé and the BMW 120d Coupé are significantly lighter than comparable four-cylinder diesels. Most of this reduction in weight comes from the aluminium crankcase with its thermally joined grey-cast-iron cylinder liners.
This optimisation of engine weight and design ensured from the start in the development process has a positive impact not only on the car’s economy, since the reduction of engine weight also enhances the car’s harmonious distribution of axle load in the interest of even better agility.
Yet a further point is that both diesel engines come as standard with a wide range of BMW EfficientDynamics improvements including Brake Energy Regeneration, the Auto Start Stop function and a gearshift point indicator (on the manual transmission models), active aerodynamics and on-demand management of the engine’s ancillary units. And as representatives of a new generation of diesel engines, the power units featured in the BMW 123d Coupé and the BMW 120d Coupé naturally come as standard with a particulates filter close to the engine.
BMW 123d Coupé setting a new benchmark in output per litre.
The four-cylinder power unit featured in the BMW 123d Coupé, the first diesel in this segment with Variable Twin Turbo technology, develops maximum output of 150 kW/204 hp at 4,400 rpm from engine displacement of 1,995 cc. This makes it the first all-aluminium diesel engine in the world with more than 100 hp output per litre. Peak torque of 400 Newton-metres/295 lb-ft, in turn, comes at just 2,000 rpm.
Variable Twin Turbo technology offers particular efficiency in boosting the power of the engine. Referred to also as multi-stage turbocharging, this system is made up of a small and a large exhaust gas turbocharger working together in supplying intake air to the four cylinders. Benefiting from its low inertia, the small turbocharger ensures superior torque and pulling force from low engine speeds just above the idling level. At higher engine speeds the larger turbine cuts in to provide extra power and torque, the big advantage of this interplay of two turbochargers being the complete avoidance of the usual “turbo gap”.
The 2.0-litre power unit featured in the BMW 123d Coupé comes with common-rail direct fuel injection incorporating piezo-injectors operating at a pressure of 2,000 bar. With fuel being injected into each cylinder through three openings in up to three portions, the flame spreads smoothly and gently through the fuel/air mixture during the operating stroke, benefiting above all the running smoothness of the diesel engine.
Offering a top speed of 238 km/h (148 mph) and accelerating to 100 km/h in 7.0 seconds, the new BMW 123d Coupé guarantees remarkable perfor-mance on the road. And in combination with average fuel consumption in the EU test cycle of just 5.2 litres/100 kilometres (equal to 54.3 mpg imp), this kind of performance clearly proves the consistent implementation of the BMW EfficientDynamics development strategy.
With CO2 emissions of just 138 grams per kilometre, the new BMW 123d Coupé ranks right at the top also in this respect. Indeed, it is the first car with more than 200 hp to offer a CO2 emission rating of less than 140 grams per kilometre.
High power and low CO2 emissions on the BMW 120d Coupé.
The power unit of the new BMW 120d Coupé also features a very sophisti-cated turbocharger system in technical terms: The 2.0-litre four-cylinder comes with one single exhaust gas turbocharger fitted with adjustable turbine blades to ensure optimum development of power throughout the entire load range. An electric actuator motor serves in this case to adjust the turbine blades to current load requirements within fractions of a second, ensuring both a spontaneous and direct response at low engine speeds and high output under full load. Maximum turbocharger pressure is 2.55 bar, with diesel fuel being delivered into the combustion chambers by piezo-injectors at a pressure of 1,800 bar.
Displacing 1,995 cubic centimetres, the four-cylinder develops a muscular 130 kW/177 hp maximum output at 4,000 rpm, with peak torque of 350 Newton-metres/258 lb-ft maintained consistently between 1,750 and 3,000 rpm. This kind of power gives the new BMW 120d Coupé a top speed of 226 km/h (140 mph), with acceleration to 100 km/h in 7.6 seconds. Fuel consumption of just 4.9 litres/100 kilometres (equal to 57.6 mpg imp) and CO2 emissions of 130 grams per kilometre are both exceptionally low.
The new generation of four-cylinder diesel engines is also characterised by a unique standard of smoothness and running refinement. As a result, the less experienced driver or the driver not that well acquainted with the car – for example in the case of a rental car – will hardly feel the difference any more versus a petrol-engined model.
Precisely this is why the new BMW 123d Coupé and the new BMW 120d Coupé come with false filling protection requiring the driver to use a diesel filling pump at the filling station, since a petrol pump would not fit due to the entry lock only a standardised diesel filling pump is able to open.
Intelligent energy management with Brake Energy Regeneration.
The power units of the new BMW 1 Series Coupé offer a particularly impressive combination of dynamics, efficiency and running refinement. All four engines provide superior power on even less fuel and exhaust emissions reduced to an even lower level than before. This is achieved, first, by modifications within the engine itself serving to reduce friction forces, through the re-design of the combustion chambers, optimisation of the fuel/air mixing process using common-rail fuel injection on the turbodiesels, High Precision Injection on the gasoline model, as well as precise management of both fuel combustion and the supply of air.
The second major area of improvements involves the vehicle itself, again helping to reduce fuel consumption by a significant margin: As an example, all variants of the BMW 1 Series Coupé come with Brake Energy Regene-ration using intelligent generator control. In this case electric power for the car’s on-board network is generated only in overrun and when the driver applies the brakes. When accelerating, on the other hand, the generator is generally disconnected in order to provide extra drive power.
This concept of intelligent energy management is comparable to the operation of power stations with storage technology, where low-cost energy is stored during the night in reservoirs at higher elevations and then regained during the day in order to meet peak requirements.
Applying this concept to Brake Energy Regeneration in the new BMW 1 Series Coupé, the system is able to determine which driving phases are appropriate for generating electric power then stored in the battery and subsequently fed into the on-board network when required.
To maximise the service life of the battery and provide compensation for the greater flow of energy, the intelligent energy management system, interacting with new AGM battery technology, uses so-called regeneration cycles. In this case the battery is charged with higher voltage pulses from time to time after a certain cycle of charging and discharging, thus ensuring appropriate phases of regeneration.
Auto Start Stop for shorter idling periods.
On the manual gearbox versions of the BMW 1 Series Coupé with a four-cylinder power unit, Auto Start Stop serves to enhance efficiency above all in city traffic: As soon as the driver shifts to idle and takes his foot off the clutch, the electronic engine control unit will automatically switch off the engine, reducing fuel consumption at red traffic lights, for example, to zero. Then, to start the engine again, all the driver has to do is press the clutch pedal, with the engine coming back on immediately without any further intervention.
Gearshift point indicator for low-consumption motoring.
Electronic engine control in the new BMW 1 Series Coupé offers substantial assistance in the effective use of fuel also while driving: A gearshift point indicator – that is an arrow symbol coming on in the instrument cluster and specifying the optimum driving gear – shows the driver the ideal point for shifting gears in the interest of maximum fuel economy.
Further reduction in fuel consumption through on-demand management of ancillary units.
Further improvements serving to save fuel likewise do not require any intervention by the driver: The BMW 1 Series Coupé featuring one of the new four-cylinder diesel engines, for example, comes with active control of the air flaps in the radiator grille. So whenever the engine needs less cooling the flaps are closed for a measurable improvement of aerodynamics and, as a result, a further reduction of fuel consumption.
A further point is that numerous ancillary units on the four-cylinder engines are operated only on-demand, again in the interest of minimum energy consumption. As an example, energy is used for the EPS Electric Power Steering with its integrated Servotronic function only when steering assistance is really required or desired by the driver. When driving in a straight line or at a constant angle in bends, the servo unit does not take up any energy. Another example is the electric coolant pump operating as a function of engine speed and temperature only when really required. Consuming just 200 W as a result of this technology, the electric coolant pump requires only about one-tenth of the drive energy consumed by a conventional pump.
Last but certainly not least, the belt drive on the climate compressor is disengaged whenever appropriate by a clutch, with the compressor automatically being disconnected when the air conditioning is switched off. This reduces the drag forces exerted by the compressor to a minimum and gives the engine an even higher degree of efficiency.
100 per cent sports feeling also with automatic transmission.
As an alternative to the six-speed manual gearbox, optional automatic transmission is available to begin with on the BMW 120d Coupé and will later be featured on the other engine variants, too. And like the manual gearbox, this automatic transmission comes with six gears, using an innovative converter complete with an integrated torsion damper.
This reduces energy losses and shortens the reaction and gearshift times on the transmission, the direct connection of engine and transmission serving to enhance the dynamic character of the car and ensure a precise gearshift.
The driver may even shift down quickly by skipping one or several gears, simply by kicking down the gas pedal for particularly fast and dynamic acceleration. The automatic transmission comes complete with a Steptronic function providing not only the usual automatic mode, but also a manual gearshift either from the gear selector lever or by optional shift paddles on the steering wheel – so that the new BMW 1 Series Coupé offers that sports feeling so typical of BMW also with automatic transmission.
