2014 Mercedes-Benz CLA45 AMG

The basis for these impressive figures is provided by the high-tech package which has been put together by Mercedes-AMG. As a high-performance engine belonging to the BlueDIRECT family, the four-cylinder turbo engine features spray-guided direct petrol injection via piezo injectors positioned centrally in the four combustion chambers. The combination of multiple fuel injection and multiple spark ignition improves fuel utilisation and increases thermodynamic efficiency substantially, leading to lower exhaust emissions. Other highlights include the gravity-die sandcast all-aluminium crankcase, weight-optimised crank assembly with forged steel crankshaft and forged pistons with friction-optimised piston rings, NANOSLIDE cylinder wall technology, air-water charge air cooling, generator management and ECO start/stop function.

Twin-scroll turbochargers and AMG sports exhaust system with exhaust flap

Mercedes-AMG addresses the essential challenges concerning the response of small-displacement turbo engines by means of a twin-scroll turbocharger, maximum derestriction of the exhaust system and an innovative injection strategy. The twin-scroll technology provides for a more spontaneous build-up of charge pressure, making effective use of exhaust gas back pressure, exhaust gas temperature and exhaust gas impulse. This results in a swifter build-up of torque right from the lower rev range. As a positive side-effect, the twin-scroll technology also benefits fuel consumption and exhaust emissions. With a maximum charge pressure of 1.8 bar, the AMG 2.0-litre four-cylinder turbo engine leads the field in this respect, too.

The AMG sports exhaust system features large pipe cross-sections and an automatically controlled exhaust flap. This technology, which is familiar from the SLK 55 AMG, reconciles the two apparently conflicting aims of tangible dynamism and hallmark Mercedes comfort on long journeys. The flap is continuously adjusted by map control according to the power called up by the driver, load status and engine speed. The AMG sports exhaust system emits a fascinating, full engine sound that is particularly impressive during powerful acceleration.

An AMG Performance exhaust system with exhaust flap is available as an option for the A 45 AMG. This provides for an even more emotional and striking engine sound when the throttle is open and during gear shifting. The double-declutching function during downshifting and the interruption of ignition and injection during upshifting under full load produce a particularly throaty sound with the AMG Performance exhaust system and create a level of emotionality which is otherwise the preserve of engines with more than four cylinders.

High-performance cooling system with components from the SLS AMG

The high driving dynamics of the CLA45 AMG call for a highly effective cooling system. On the basis of the components from the SLS AMG, a low-temperature circuit is additionally deployed for air-water charge air cooling of the four-cylinder turbo engine. The cooler extending across the complete front level of the cooling module is supplemented by an additional cooler in the wheel arch. Together with the charge air cooler, which is connected in series, a high-performance electric pump ensures the required flow through the water coolers located behind the large intake ports. This provides for ideal cooling of the highly compressed charge air, thereby contributing towards optimum engine performance.

The cooling of the transmission oil is integrated into the water cooling circuit for the engine. The water cooler positioned behind the front apron is supported by the heat exchanger which is fitted directly on the transmission and supplied with cooling water as required by means of an auxiliary pump.

“One man, one engine”: a tradition of hand-built excellence

As is the case with all eight- and twelve-cylinder engines, the new AMG four‑cylinder turbo engine is hand-built according to the traditional AMG philosophy of “one man, one engine”. An exclusive assembly line has been set up for the new AMG engine at the Mercedes-Benz engine production plant in Kölleda – where all BlueDIRECT four-cylinder engines are built for the A-Class and B-Class models. A characteristic feature of the “one man, one engine” production process is the AMG engine plate bearing the signature of the responsible engine fitter. Apart from serving as an AMG hallmark confirming superlative production quality, the AMG engine plate also attests to the peerless DNA of Mercedes-Benz’s high-performance brand.

AMG SPEEDSHIFT DCT 7-speed sports transmission

Dual clutch transmission and all-wheel drive – the drive package on board the new CLA45 AMG is a demonstration of high-end engineering prowess. The AMG SPEEDSHIFT DCT 7-speed sports transmission is directly flange-mounted on the transversely installed engine. Key software modules have been adopted from the SLS AMG super sports car with its inspirational power transmission concept. The dual clutch transmission of the CLA45 AMG features seven gears, three driving programmes, a double-declutching function and RACE START for optimum acceleration. The strengths of the AMG DCT sports transmission include spontaneous gear shifting without any interruption in tractive power, a tailor-made control strategy, extremely smooth and easy gear shifting and a high level of efficiency. Reinforced gear wheels provide for maximum stability. Synchroniser rings with carbon-fibre friction linings improve durability while also optimising the response time during manual gear-changing – the ideal basis for ambitious laps on cordoned-off race tracks.

“Momentary M mode” for even greater dynamism and driving enjoyment

Another special feature designed to enhance dynamic performance and driving enjoyment is the so-called “Momentary M mode”. In C and S mode, this enables the driver to activate manual mode (“M”) without having to remove a hand from the steering wheel, by pressing the “up” or “down” shift paddle once. In Momentary M mode the driver experiences the dynamism and performance of gear-shifting in manual mode in all the automatic driving programmes, with automatic up-shifting on meeting the rpm limit into the bargain. This allows the driver to devote his full attention to the vehicle’s impressive performance.

The shift times in manual mode “M” and in Sport mode “S” are similarly sporty in character to those of the SLS AMG GT super sports car. Briefly and precisely interrupting ignition and injection under full load leads to even faster gearshifts in “M” and “S”, with a more emotional sound than ever. In “C” mode (Controlled Efficiency), tangibly soft transmission and engine characteristics support a fuel-efficient and comfort-oriented driving style. In addition, in “C” mode the ECO start/stop function is active.

Performance-oriented AMG 4MATIC all-wheel drive

The CLA45 AMG comes with variable, performance-oriented AMG 4MATIC all‑wheel drive as standard. In developing this all-wheel drive, the focus was firmly on performance and dynamism. The power flux to the rear powertrain is provided by a compact power take-off unit (PTU) which is fully integrated in the 7-speed sports transmission. It does not possess an oil circuit of its own. Instead, it is supplied with lubricant from the oil circuit of the sports transmission. This configuration gives rise to substantial weight advantages in comparison to rival systems which branch off power by means of an add-on component with its own oil circuit. Together with the friction-minimised tapered roller bearings, the PTU achieves an excellent level of efficiency. As an additional bonus, the system weight of the new AMG 4MATIC all-wheel drive is up to 25 percent lighter than the all-wheel-drive versions offered by the competition.

A two-part propeller shaft transfers the power from the AMG 2.0-litre four-cylinder turbo engine to the rear axle. In the interests of favourable weight distribution, an electrohydraulically controlled multiple-disc clutch is integrated with the rear axle differential. The multiple-disc clutch immediately detects slip at the front axle. A hydraulic pump instantaneously presses the discs together and channels the engine torque to the rear wheels as necessary. All this takes place virtually without the driver noticing. To enable particularly fast response, the pump is always active and does not require to be started up each time it is needed, as is customary with other systems. Power distribution is fully variable: in normal driving, the CLA45 AMG uses front-wheel drive in the interests of optimum efficiency. When the driving dynamics so require, the variable AMG 4MATIC all-wheel drive splits the torque between front and rear axle up to a ratio of 50:50 percent. The variables influencing the power distribution ratio are vehicle speed, lateral and longitudinal acceleration, steering angle, speed difference between the individual wheels, selected gear and accelerator position.

3-stage ESP® with ESP® Curve Dynamic Assist

An exclusive feature is the interaction of the AMG 4MATIC all-wheel drive with the 3-stage ESP® and the ESP® Curve Dynamic Assist. The three ESP® stages enable the driver to vary the dynamics of the CLA45 AMG according to his individual wishes at the push of a button. The safety-oriented “ESP ON” mode supports the driver in maintaining neutral handling characteristics. The system initiates braking intervention on one or more wheels and reduces the engine torque on detecting that the operating conditions are becoming unstable.

Briefly pressing the ESP® button activates “ESP SPORT Handling” mode. This dynamically oriented driving mode applies appropriate control strategies for later ESP® intervention and increased drive torque at the rear axle. This means more fun at the wheel for drivers who are keen to exploit the vehicle’s dynamic potential. Pressing the ESP® button longer activates “ESP OFF”. In this mode, the ESP® functions are not available. ESP OFF should only be used by experienced drivers on cordoned-off race tracks. If the driver steps on the brake pedal in “SPORT Handling” mode or “ESP OFF” mode, all the safety functions of the ESP® system become available during braking.

ESP® Curve Dynamic Assist complements the ESP® system to perfection: during dynamic cornering, imperceptible braking intervention on the inside wheel gives rise to a defined yaw moment around the vertical axis, resulting in precise cornering by the CLA45 AMG and ensuring that the vehicle remains under control at all times. ESP® Curve Dynamic Assist is adapted according to the selected ESP® mode. In “ESP SPORT Handling” mode and “ESP OFF” mode it supports the driver’s wish for increased agility and driving dynamics. ESP® Curve Dynamic Assist is an additional function of the Electronic Stability Program which noticeably improves not only agility, but also active driving safety in critical conditions.

AMG sports suspension with independent front and rear axle

Like every AMG high-performance automobile, the new CLA45 AMG also incorporates sophisticated axle technology. For enhanced driving dynamics, the three-link front suspension is provided with stiffer steering knuckles and totally new elastokinematics. Newly developed, more rigid bearings are employed in the lower link plane. These provide for more agile cornering properties and more precise and direct feedback from the road surface. The more rigid bearings also lead to higher camber stiffness, enabling higher cornering speeds. In developing the complete front axle, great importance has been attached to attaining the best possible traction in highly dynamic driving.

The four-link rear axle of the CLA45 AMG is also a totally new development. In the course of optimising the elastokinematics, the strut bearings were duly adapted for maximum driving dynamics and control. The rear axle carrier is provided with more rigid bearings for increased driving stability; the subframe is rigidly connected to the body. The AMG sports suspension with specifically tuned spring/damper units and larger stabilisers provides for high lateral acceleration and a reduced rolling tendency in fast double bends. The CLA45 AMG comes as standard with AMG light-alloy wheels fitted with 235/40 R 18 tyres.

AMG speed-sensitive sports steering and AMG high-performance braking system

The electromechanical Dual Pinion AMG speed-sensitive sports steering with AMG-specific, speed-dependent power assistance and a constant steering ratio (14.5 : 1) enables high steering precision and agility. The electric motor is installed in space-saving configuration on the steering gear. The AMG high-performance braking system with ventilated and perforated brake discs all round in size 350 x 32 millimetres at the front and 330 x 22 millimetres at the rear provides for spontaneous and reliable deceleration.

Unmistakable design

Just a glance at the new CLA45 AMG makes it very clear: any resemblance to the CLS 63 AMG is absolutely intentional. The expressive design idiom of the CLA has been enhanced by Mercedes-AMG with some characteristic AMG elements – and the result is a new design icon. The sporty proportions of the CLA were there from the start , but its dynamic look is reinforced by the AMG “twin blade” radiator grille and the cross strut in the AMG front apron, both painted in matt titanium grey. The generously proportioned cooling air intakes are framed by black flics, which improve the airflow over the cooling modules positioned behind them. Bi-xenon headlamps are included as standard.

An eyecatching view from the side is ensured by the sill panels with inserts in matt titanium grey. Further elements typical of a top-of-the-range AMG model include the AMG twin-spoke light-alloy wheels, painted grey and with a high-sheen finish, plus the “TURBO AMG” lettering on the wing. Seen from the rear, the CLA45 AMG displays a distinctive AMG rear apron: this not only reveals the presence of the air outlet openings at the sides, but also incorporates a large diffuser insert and a trim section in matt titanium grey. The two chrome-plated twin tailpipes of the AMG sports exhaust system, including an exhaust flap, serve to emphasise the car’s dynamic appeal. The striking LED tail lights are a standard feature.

Dynamic, exclusive and top-quality interior

Impressive quality, high-grade materials and all the dynamism and exclusivity commonly associated with Mercedes-AMG – the interior of the CLA45 AMG leaves nothing to be desired. Sports seats in ARTICO man-made leather/DINAMICA microfibre with red contrasting topstitching, red seat belts, the multifunction steering wheel with shift paddles, the AMG DRIVE UNIT and AMG door sill panels all come as standard. Coordinating perfectly with one another are the brushed aluminium trim of the instrument panel and the five galvanised ventilation outlets. Information is provided by the AMG instrument cluster with its central colour display, the AMG main menu and the RACETIMER.

Numerous individualisation options are available for the CLA45 AMG (selection):

• AMG carbon-fibre exterior mirror housing
• AMG Exterior Carbon-Fibre package: front splitter, side sill panel inserts and trim on rear apron in genuine carbon fibre
• AMG carbon-fibre interior trim
• AMG Exclusive package
• AMG floor mats
• AMG multi-spoke light-alloy wheels in 8 x 19 fitted with 235/35 R 19 tyres, in two variants: painted in titanium grey with high-sheen finish or in matt black with high-sheen rim flange
• AMG Night package: privacy glass, black anodised beltline trim strip, black tailpipe trims in chromed finish, radiator fins in silver chrome, high-gloss black painted finish for front splitter, exterior mirrors, side sill panel inserts and rear apron trim
• AMG Performance exhaust system
• AMG Performance suspension with tauter spring/damper tuning
• AMG Performance steering wheel and E-SELECT lever, electronic main key with AMG emblem
• AMG Performance seats
• AMG wheel bolt covers in black with hub caps in central-locking look (for standard AMG light-alloy wheels only)
• Intelligent Light System
• Red-painted callipers

The sales release date for the CLA45 AMG is in July 2013; market launch will start in September. Sales price in Germany, incl. 19 percent VAT, is 56.078,75 EUR.

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