Wison Engineering signs new engineering contract for Erdos Jinchengtai coal-to-methanol project; commercializing methanol-to-olefins
5th edition of Worldwide Fuel Charter introduces Category 5 fuels for advanced emission control and fuel efficiency

Coming MINIs to feature new 3- and 4- cylinder engine line-up; adjustable dampers

P90134571
The 100 kW/134 bhp 1.5-liter MINI TwinPower Turbo in-line gasoline engine. Click to enlarge.

Future MINI models will use a new line-up of both three and four-cylinder engines. In addition, MINI will introduce electrically adjustable dampers for the first time.

A common feature of the new drive units is the MINI TwinPower turbo technology, which optimizes both performance and efficiency. In the case of the gasoline engines, this technology package includes turbocharging, direct fuel injection, variable camshaft control on the intake and outlet sides (dual VANOS) and, in the more powerful versions, fully variable valve control according to the model of the BMW Group’s patented VALVETRONIC system.

The all-new engines were designed for the transverse configuration typical of the MINI and feature a compact and lightweight design. They also comply with exhaust standard EU6. The engines are equipped with an aluminum crankshaft in a closed-deck configuration. A forged steel crankshaft with integrated balancing shaft drive, weight-optimized piston and forged conrod contributes to the high level of performance within the engine through reduced frictional coefficients.

The three-cylinder engines each have a countershaft to enhance smooth operation, while the four-cylinder model has two such shafts that counter-rotate. The cylinder head in all engine variants is made of aluminum. There are further similarities in terms of the layout of the ancillary units and the design of the map-regulated oil pump and the mechanically activated coolant pump. As the coolant pump supports both the generator and the climate compressor, the drive units have a more compact design.

For the market launch of the new drive generation, MINI is presenting a three-cylinder combustion engine that generates an output of 100 kW/134 bhp from a cubic capacity of 1.5 liters and a 141 kW/189 bhp variant of the newly developed four-cylinder combustion engine that has a cubic capacity of 2.0 liters.

The 1.5 liter three-cylinder engine reaches its maximum torque of 220 N·m (162 lb-ft) at an engine speed of 1,250 rpm; this can be increased briefly to 230 N·m (170 lb-ft) by means of the overboost function. The 141 kW/189 bhp four-cylinder model actually achieves a torque of 280 N·m (206 lb-ft) with the same engine speed, and 300 N·m (221 lb-ft) with overboost. The maximum speed of all new gasoline engines is 6,500 rpm.

The engine’s sporty character is favored by the position of the turbocharger integrated in the exhaust manifold. The short path of the exhaust stream enables the charging system to be activated promptly and effectively. In addition, the emissions pattern of the engines is optimized by the positioning of the catalytic converter and an electronically regulated waste gate.

An efficient and precisely dosed fuel supply system facilitates direct injection with centrally positioned injectors between the valves and directly next to the spark plugs. The electronic control for camshaft positioning and the stroke of the intake valves further optimize the responsiveness and the consumption and emissions readings of the new gasoline engines for MINI.

Newly developed manual and automatic gearboxes will further enhance the efficiency of the drive technology. The new manual gearboxes feature an innovative gear sensor which adapts the engine speed when shifting gears. This permits fast and sporty shifting with always the right engine speed available during gear shifts.

The automatic start-stop function can also be used in future MINI models in conjunction with the automatic gearbox, avoiding unnecessary fuel consumption when stopped at junctions or when caught in heavy traffic. For cars equipped with a navigation system, gear selection can be adapted to the current route. This way, the suitable gear is selected before reaching junctions or before cornering.

Chassis. The complete redesign of the chassis for future MINI models continues to focus on the tried-and-tested structure of the single-link spring strut axle at the front, and the multi-link rear axle—unique among MINI’s competitors. It also includes component optimizations in terms of material choice and geometry.

The dampers on the front and rear axles are uncoupled from the bodywork by means of complex struts. In combination with the reduction of the unsprung inertial masses, this makes it possible to increase both agility and driving comfort.

Newly developed and aerodynamically optimized light alloy wheels are manufactured in a forging process requiring the use of less material.

In its latest incarnation, the front single-link spring strut axle features increased component rigidity. In combination with a modified axial kinematic movement, this creates ideal conditions for particularly agile maneuverability and steering control that is largely freed from the influence of the drive mechanism. The wider track gauge also makes a further contribution to optimizing sporty characteristics.

Consistency in lightweight design also influenced driving performance. The use of aluminum in the pivot bearing and high tensile steels in the front axle bearing and in the transverse rocker arms reduces the unsprung inertial masses. The innovative torque roll axial bearing enables both agility and comfort to be tangibly increased. This component consists of an engine and a transmission bearing that together absorb the weight of the engine and also support the torque in conjunction with the engine swivel support. The engine block is hydraulically attenuated, further enhancing the increase in comfort because this design prevents the engine from surging under the influence of uneven road surfaces.

By further developing the multi-link rear axle, MINI is building on its position in the competitive field. Key changes—wider track gauge, the use of high-strength steels and greater rigidity in the wheel suspension—take place in tandem with the modifications to the front axle. The spatial design of the rear axle also leads to improved entry comfort and to more space in the rear as well as a larger luggage compartment volume which is also easier to load.

Electromechanical power steering. The next generation of the EPS (Electronic Power Steering) used for MINI models offers speed-dependent support for the steering force. In the future it will take less steering force to operate this, while the system will also meet the requirements for the use of a parking assist function.

With the complex wheel suspension system, the steering ratio can be implemented very directly. Likewise, the optimization of the front axle has a direct impact on the steering, as it facilitates a sensitive steering style when negotiating curves in a sporty style. This effect is further enhanced by the use of torque steer compensation. This torque steering compensation counteracts a tendency towards self-steering in powerful front-wheel drive vehicles due to differences in torque between the right and left front wheels.

In the future, active rotational damping will provide for gentler and therefore more precisely controllable vehicle reactions in rapid evasion manoeuvres and when negotiating particularly sporty bends.

Adjustable dampers. In an effort to emphasize the MINI character even more, the spring and damper adjustment will be optimized. On the front axle, spring struts made of aluminum and steel and two-pipe compression dampers with coated pistons and a degressive damper characteristic curve are used. The support bearings on the front and rear axles will have three paths in future.

The characteristic curves of the support bearing and additional springs have also been optimized on a functional basis, as have the helical springs installed on both axes. The stabilizers on the front and rear axles have holdings bearings and will have a tubular design, helping to reduce weight in the chassis area.

In addition, MINI will be introducing adjustable dampers for the first time. The electric control of the damper valves allows the characteristic response to uneven road surface to be varied. Two characteristic curves are available for adjusting the damper and these can be activated at the flip of a switch. The traction and compression level in the shock absorber can be adjusted by selecting the appropriate setting. Depending on the driver’s preferences, it is possible to choose either a sporty or a balanced, comfortable chassis. This means that it is possible to enjoy greater driving comfort in poor road conditions or a sporty driving style on an even road surface.

Lightweight construction. The focus of developments in the body area is on structural improvements that have a positive influence on both driving features and crash performance; the use of second-generation high-strength multi-phase steels plays a key role. Their forming properties allow for much more complex structures than would be possible with conventional materials, while still permitting no compromise on strength. Parts that are of particular relevance to structural rigidity are made from micro-alloyed steels. In addition, hot-formed steels are used in the safety-related zones.

Tailored welded blanks and tailored rolled blanks also contribute to the optimization of weight. Welded and rolled sheet metal joints will be widely used for the first time in cars from the small vehicle segment. The reinforcement of the B pillars with a coating of galvanized, hot-formed steel, which acts as a cathodic anti-corrosion finish, means that additional, weight-increasing measures could be dropped.

Comments

Nick Lyons

Missing word: The engines are equipped with an aluminum crankshaft in a closed-deck configuration. A forged steel crankshaft...

Should be "...aluminum crankshaft housing in a closed-deck configuration..."

Arnold

Axes: plural of axis.

Pictures of the suspension arrangement would be worth a thousand words.


kelly

Nick, thanks for missing word.

As is sounds like one tough newly treated piece of aluminum(or short-lived engine)..

The comments to this entry are closed.