Source by: http://www.caradvice.com.au/40673/2011-mclaren-mp4-12c-revealed/ The first McLaren to be released since the manufacturer’s groundbreaking 1993 F1 model, the MP4-12C, is due to go on sale early in 2011.
The two-seater will have a price tag of roughly £160,000 (AUD$306,000) and utilise a McLaren built (M838T) 3.8-litre 90-degree V8 engine, developing “around 450kW and 600Nm”, as means of motivation.
The engine is twin-turbocharged unit with an 8500rpm red-line featuring a dry sump and flat plane crank that drives the rear wheels via a seven-speed dual-clutch gearbox.
McLaren claims 80 per cent of the MP4-12C’s torque will be available from below 2000rpm which should see low three second 0-100km/h times and a top speed in excess of 320km/h.
Considering the MP4-12C will utilise a carbon fibre MonoCell skeleton (weighing in at just 80kg), with aluminium and SMC plastic panels, this should see a kerb weight of roughly 1300 kilograms.
The car will feature conventional brakes with forged aluminium hubs which believe it or not are some 8kg lighter than ceramic units.
Braking is further assisted by an air brake that pops up at speed to improve stopping ability.
Entry to the cabin is via dihedral doors which are touchpad operated. The seating is said to be “thin” but spot on in terms of support.
An upright seven-inch multimedia screen sits in the centre console while the view out the front windscreen is clear of obstruction.
Driver aids include switchable ESC, launch control, selectable throttle response (normal, sport & high performance) as well as settings to adjust gearshift timing and suspension damping.
I’m old enough to remember when Mercedes used the tagline “engineered like no other car in the world,” and no one questioned it. When the 1986 W124 E-Class was introduced, Car & Driver proclaimed it “the best car in the world.” In the quarter-century since, Mercedes’ position in the automotive pecking order has become less certain. Lexus came out of nowhere, and BMW has managed to successfully expand upward from the 3-Series and to become a provider of luxury as well as sport. For 2010 Mercedes has totally redesigned the E-Class. Any chance it’s 1986 all over again?
Back to basics?The styling of the 1986 W124 E-Class was timeless. Noting that the marque’s traditional virtues were no longer bringing in the buyers, Mercedes grafted four oval headlights onto the mid-1990s W210 E-Class to communicate “we’re not stodgy.” That ploy worked for a couple of years, after which many people were wishing the W124 had never been replaced. With the 2003 W211, timeless styling returned, and it hurt. Surrounded by Audiesque grilles and Bangled bodysides, no luxury sedan was easier to lose in a crowd. So, with the 2010 W212 E-Class, Mercedes has again opted for road presence and distinctive styling. Specifically, the new car’s chunkier shape is adorned with a quartet of rectangular headlights and pointless rear fender bulges. The W211 is easily the more beautiful car, but the W212 looks much more like $55,000, even if the design of the hood makes it appear misaligned.
The restyled E-Class interior resembles that of the current C-Class. The shapes are blocky rather than flowing and organic, and might appear overly basic or even cheap were it not for the obvious quality of the materials and subtle detailing. Very German.
Following BMW’s lead, the transmission shifter is an electronic stalk on the steering column, freeing up console real estate for an iDrive-like controller. While a console-mounted shifter no longer makes much functional sense, a car does seem less sporty without one.Nip-tuck, parry-thrust. The W212 continues Mercedes’ tradition of a relatively high driving position, for better forward visibility than in an Audi or BMW. The front seats continue another Mercedes tradition: they’re much firmer than those in a Volvo or Lexus. While shaped well for support, even the lateral variety, these seats lack the plush feeling many people will expect in a luxury sedan.
The W212 E-Class’s rear seat is an improvement over that in the W211, but continues to lag those in the BMW 5-Series and Infiniti M in terms of comfort and space. The thinking at Mercedes-Benz seems to be that those seeking an adult-worthy rear seat should spring for the S-Class. One thing the rear seat does do (optionally) that those in Asian competitors don’t: fold to expand the trunk.
The great majority of buyers in the United States will opt for the base engine, a 268-horsepower 3.5-liter V6, and for good reason: it’s more than adequate. You can get just as much power in an Accord these days, and some competing sixes offer 300+ horsepower. But the fact of the matter is that most drivers won’t come close to tapping out the E350’s power potential in 99 percent of their driving. This wouldn’t be the case with an old-style four-speed automatic, but when there are seven ratios to select from the engine is always in its powerband. Unlike some earlier iterations of this transmission, the one in the W212 shifts smoothly and with an appropriate frequency. Mercedes’ pricing can be baffling. In some cases an AMG body kit, sport suspension tuning, and upsized wheels can run over five grand. In other cases—including the 2010 E350—the sport treatment is no extra charge. Sport Package for free? That’s an easy choice.
KuhlThe sport-suspended chassis behaves well, with good balance, admirable composure over rough patches, and minimal lean in hard turns. Through the seat of one’s pants, the car feels tight and precise. Then there’s the steering. In a word, it’s dead. Weighting varies from overly light to artificial. Road feel is absent. The suspension might be excellent, but this steering dashes any chance of a driver connecting with this car.
The E-Class’s ride is neither as firm as in a BMW 5-Series nor as absorbent as in a Lexus GS. It doesn’t feel cushy, but there’s no harshness. Nor are there any of the untoward, indecisive jiggles that occasionally mar the ride of the upstart Hyundai Genesis. The solid, planted feel Mercedes has traditionally been known for is certainly present in this car. As in just about any luxury sedan these days (with the notable exception of the Audi A6), noise levels are low. The new Mercedes-Benz E-Class looks and feels solid and expensive. But if Mercedes wants to regain its earlier reputation, it needs to offer more than this. Aspects of the styling will appear dated by the time the lease is over. But that’s common in the post-Bangle era. More troubling, the combination of overly firm seats with zombie steering means that the new W212 E-Class excels as neither a luxury sedan nor a sport sedan. Who is this car for? Do even luxury sedan buyers want to feel entirely disconnected from the driving experience? Mercedes has been making cars longer than anyone else has. So why can’t they provide a decent steering system?
VTEC is also an abbreviation for the verocytotoxin-producing Escherichia coli strain O157:H7.
VTEC (Variable Valve Timing and Lift Electronic Control) is a valvetrain system developed by Honda to improve the volumetric efficiency of a four-stroke internal combustion engine. This system uses two camshaft profiles and electronically selects between the profiles. It was invented by Honda R&D engineer Ikuo Kajitani. It can be said that VTEC, the original Honda variable valve control system, originated from REV (Revolution-modulated valve control) introduced on the CBR400 in 1983 known as HYPER VT EC. VTEC was the first system of its kind, though other variable valve timing and lift control systems have been produced by other manufacturers (MIVEC from Mitsubishi, VVTL-i from Toyota, VarioCam Plus from Porsche, VVL from Nissan, etc).
DOHC VTEC
Honda's system is a simple method of endowing the engine with multiple camshaft profiles optimized for low and high RPM operations. Instead of one cam lobe actuating each valve, there are two: one optimized for low-RPM stability & fuel efficiency; the other designed to maximize high-RPM power output. Switching between the two cam lobes is controlled by the ECU which takes account of engine oil pressure, engine temperature, vehicle speed, engine speed and throttle position. Using these inputs, the ECU is programmed to switch from the low lift to the high lift cam lobes when the conditions mean that engine output will be improved. At the switch point a solenoid is actuated which allows oil pressure from a spool valve to operate a locking pin which binds the high RPM cam follower to the low rpm ones. From this point on, the poppet valve opens and closes according to the high-lift profile, which opens the valve further and for a longer time. The switch-over point is variable, between a minimum and maximum point, and is determined by engine load. The switch back from high to low rpm cams is set to occur at a lower engine speed than the up-switch to avoid a situation in which the engine is asked to operate continuously at or around the switch-over point.
Introduced as a DOHC system in the 1989 Honda Integra and Civic CRX SiR models sold in Japan and Europe, which used a 160 bhp (120 kW) variant of the B16A engine. The US market saw the first VTEC system with the introduction of the 1991 Acura NSX, which used a DOHC VTEC V6 with 290 bhp (220 kW). DOHC VTEC engines soon appeared in other vehicles, such as the 1992 Acura Integra GS-R (B17A 1.7 liter engine). And later in the 1993 Honda Prelude VTEC (H22 2.2 liter engine with 195hp) and Honda Del Sol VTEC (B16 1.6 liter engine). Honda has also continued to develop other varieties and today offers several varieties of VTEC, such as i-VTEC and i-VTEC Hybrid.
SOHC VTEC
As popularity and marketing value of the VTEC system grew, Honda applied the system to SOHC (Single Over Head Cam) engines, which shares a common camshaft for both intake and exhaust valves. The trade-off was that Honda's SOHC engines only benefitted from the VTEC mechanism on the intake valves. This is because VTEC requires a third center rocker arm and cam lobe (for each intake and exhaust side), and in the SOHC engine, the spark plugs are situated between the two exhaust rocker arms, leaving no room for the VTEC rocker arm. Additionally, the center lobe on the camshaft can only be utilized by either the intake or the exhaust, limiting the VTEC feature to one side.
However, beginning with the J37A4 3.7L SOHC V6 engine introduced on all 2009 Acura TL SH-AWD models, SOHC VTEC was incorporated for use with intake and exhaust valves. The intake and exhaust rocker shafts contain primary and secondary intake and exhaust rocker arms, respectively. The primary rocker arm contains the VTEC switching piston, while the secondary rocker arm contains the return spring. The term "primary" does not refer to which rocker arm forces the valve down during low-RPM engine operation. Rather, it refers to the rocker arm which contains the VTEC switching piston and receives oil from the rocker shaft.
The primary exhaust rocker arm contacts a low-profile camshaft lobe during low-RPM engine operation. Once VTEC engagement occurs, the oil pressure flowing from the exhaust rocker shaft into the primary exhaust rocker arm forces the VTEC switching piston into the secondary exhaust rocker arm, thus locking both exhaust rocker arms together. The high-profile camshaft lobe which normally contacts the secondary exhaust rocker arm alone during low-RPM engine operation is able to move both exhaust rocker arms together which are locked as a unit.
The secondary intake rocker arm contacts a low-profile camshaft lobe during low-RPM engine operation. Once VTEC engagement occurs, the oil pressure flowing from the intake rocker shaft into the primary intake rocker arm forces the VTEC switching piston into the secondary exhaust rocker arm, thus locking both intake rocker arms together. The high-profile camshaft lobe which normally contacts the primary intake rocker alone during low-RPM engine operation is able to move both intake rocker arms together which are locked as a unit.
The difficulty of incorporating VTEC for both the intake and exhaust valves in a SOHC engine has been removed on the J37A4 by a novel design of the intake rocker arm. Each exhaust valve on the J37A4 corresponds to one primary and one secondary exhaust rocker arm. Therefore, there are a total of twelve primary exhaust rocker arms and twelve secondary exhaust rocker arms.
However, each secondary intake rocker arm is shaped similar to a "Y" which allows it to contact two intake valves at once. One primary intake rocker arm corresponds to each secondary intake rocker arm. As a result of this design, there are only six primary intake rocker arms and six secondary intake rocker arms.
VTEC-E
It is a version of SOHC VTEC, which was used to increase efficiency at low RPM. At low RPM, one of the two intake valves is only allowed to open a very small amount, increasing the fuel/air atomization in the cylinder and thus allowing a leaner mixture to be used. As the engine's speed increases, both valves are needed to supply sufficient mixture. A sliding pin, which is pressured by oil, as in the regular VTEC, is used to connect both valves together and allows the full opening of the second valve.
3STAGE VTEC
It is a version using 3 different cams to control valve timing and lift. At low RPM, only 1 intake valve is used; at medium RPM, 2 intake valves are used; at high RPM, high speed valve cam is used to increase power...
i-VTEC-(intelligent-VTEC introduced continuously variable camshaft phasing on the intake cam of DOHC VTEC engines. The technology first appeared on Honda's K-series four cylinder engine family in 2001 (2002 in the U.S.). In the United States, Honda first debut the technology on the 2003 Honda Civic Si EP3 with the economy version.
Valve lift and duration are still limited to distinct low- and high-RPM profiles, but the intake camshaft is now capable of advancing between 25 and 50 degrees (depending upon engine configuration) during operation. Phase changes are implemented by a computer controlled, oil driven adjustable cam gear. Phasing is determined by a combination of engine load and rpm, ranging from fully retarded at idle to somewhat advanced at full throttle and low rpm. The effect is further optimization of torque output, especially at low and midrange RPM.
The K-Series motors have two different types of i-VTEC systems implemented. The first is for the performance motors like in the RSX Type S or the TSX and the other is for economy motors found in the CR-V or Accord. The performance i-VTEC system is basically the same as the DOHC VTEC system of the B16A's, both intake and exhaust have 3 cam lobes per cylinder. However the valvetrain has the added benefit of roller rockers and continuously variable intake cam timing. The economy i-VTEC is more like the SOHC VTEC-E in that the intake cam has only two lobes, one very small and one larger, as well as no VTEC on the exhaust cam. The two types of motor are easily distinguishable by the factory rated power output: the performance motors make around 200 hp (150 kW) or more in stock form and the economy motors do not make much more than 160 hp (120 kW) from the factory.
An additional version of i-VTEC was introduced on the 2006 Honda Civic's R-series four cylinder SOHC engines. This implementation uses the so-called "economy cams" on one of the two intake valves of each cylinder. The "economy cams" are designed to delay the closure of the intake valve they act upon, and are activated at low rpms and under light loads. When the "economy cams" are activated, one of the two intake valves in each cylinder closes well after the piston has started moving upwards in the compression stroke. That way, a part of the mixture that has entered the combustion chamber is forced out again, into the intake manifold. That way, the engine "emulates" a lower displacement than its actual one (its operation is also similar to an Atkinson cycle engine, with uneven compression and combustion strokes), which reduces fuel consumption and increases its efficiency. During the operation with the "economy cams", the (by-wire) throttle butterfly is kept fully open, in order to reduce pumping losses. According to Honda, this measure alone can reduce pumping losses by 16%. In higher rpms and under heavier loads, the engine switches back into its "normal cams", and it operates like a regular 4 stroke Otto cycle engine. This implementation of i-VTEC was initially introduced in the R18A1 engine found under the bonnet of the 8th generation Civic, with a displacement of 1.8 L and an output of 140 PS (100 kW; 140 hp). Recently, another variant was released, the 2.0 L R20A2 with an output of 150 PS (110 kW; 150 hp), which powers the EUDM version of the all-new CRV
With the continued introduction of vastly different i-VTEC systems, one may assume that the term is now a catch-all for creative valve control technologies from Honda.
i-VTEC VCM- In 2003, Honda introduced an i-VTEC V6 (an update of the J-series) that includes Honda's cylinder deactivation technology which closes the valves on one bank of (3) cylinders during light load and low speed (below 80 km/h (50 mph)) operation. The technology was originally introduced to the US on the Honda Odyssey minivan, and can now be found on the Honda Accord Hybrid, the 2006 Honda Pilot, and the 2008 Honda Accord.
i-VTEC VCM was also used in 1.3L 4-cylinder engines used in Honda Civic Hybrid.
i-VTEC i
It is a version of i-VTEC with direct injection.
It was first used in 2003 Honda Stream.
AVTEC
The AVTEC (Advanced VTEC) engine was first announced in 2006. It combines continuously variable valve lift and timing control with continuously variable phase control. Honda originally planned to produce vehicles with AVTEC engines within next 3 years.
Although it was speculated that it would first be used in 2008 Honda Accord, the vehicle only used the older engines.
A related US patent (6,968,819) was filed in 2005-01-05.
DTEC- It is a version for diesel engine.
i-DTEC- It is a variant of i-CTDi diesel engine with exhaust gas recirculation, NOx catalytic storage, 2000bar injector.
The engine was unveiled in 2008 NAIAS.
The engine was first introduced in European 2008 Honda Accord as Honda N engine.
Honda originally announced the North American version of i-DTEC would be available in 2009 Acura vehicles, but it has yet to be introduced for that calendar year.
VTEC in motorcycles- Apart from the Japanese market-only Honda CBR400F Super Four HYPER VTEC, introduced in 1983, the first worldwide implementation of VTEC technology in a motorcycle occurred with the introduction of Honda's VFR800 sportbike in 2002. Similar to the SOHC VTEC-E style, one intake valve remains closed until a threshold of 7000 rpm is reached, then the second valve is opened by an oil-pressure actuated pin. The dwell of the valves remains unchanged, as in the automobile VTEC-E, and little extra power is produced but with a smoothing-out of the torque curve. Critics maintain that VTEC adds little to the VFR experience while increasing the engine's complexity.
The engine is twin-turbocharged unit with an 8500rpm red-line featuring a dry sump and flat plane crank that drives the rear wheels via a seven-speed dual-clutch gearbox.
Considering the MP4-12C will utilise a carbon fibre MonoCell skeleton (weighing in at just 80kg), with aluminium and SMC plastic panels, this should see a kerb weight of roughly 1300 kilograms.
The car will feature conventional brakes with forged aluminium hubs which believe it or not are some 8kg lighter than ceramic units.
Braking is further assisted by an air brake that pops up at speed to improve stopping ability.
Entry to the cabin is via dihedral doors which are touchpad operated. The seating is said to be “thin” but spot on in terms of support.
An upright seven-inch multimedia screen sits in the centre console while the view out the front windscreen is clear of obstruction.
Driver aids include switchable ESC, launch control, selectable throttle response (normal, sport & high performance) as well as settings to adjust gearshift timing and suspension damping.
