With the first “customer car” already in the assembly bay at Woking, McLaren has finally released full technical details of its MP4-12C - and they make fascinating reading.
This is not just the launch of a new car, says McLaren Automotive chairman Ron Dennis, it's the launch of a new car company.
“McLaren's first and founding principle was to compete successfully in motor sport and particularly Formula One.
“That goal has taken us to great heights but we have also long held the dream of building a range of innovative McLaren sports cars, taking the elements of Formula 1 principles, processes and performance, and adding the requirements of quality, efficiency, comfort and reliability.
“McLaren's modern history began 30 years ago with 50 people dedicated to winning Grands Prix. McLaren now employs about 1500 people, all passionate about being the best - and about launching a new car company and our first car.”
McLaren Automotive managing director, Antony Sheriff, summed up the focus for McLaren Automotive: 'The overriding principle is that every car will be 'pure' McLaren. Each component has been designed and produced to McLaren's specification to meet the requirements of the 12C
There are no carryover components, because they just weren't good enough. Similarly, our test programmes and production processes are new. We considered everything from a blank sheet of paper; being “as good” as everybody else wasn't good enough - we had to be the best. This approach has given us a remarkable car with ground-breaking performance in all areas.”
The McLaren MP4-12C, he says, has redefined high-performance sports car benchmarks.
Headline figures include:
Power: 442kW at 7000rpm
Torque: 600Nm from 3000-7000rpm.
CO2 emissions: 279g/km (equivalent to 11.7 litres/100km).
Weight of carbon-fibre chassis: 75kg.
Dry weight (with lightweight options): 1301kg.
Power/weight (with lightweight options): 340kW/ton.
0 - 100km/h: 3.3sec (3.1sec on optional Corsa tyres).
0 - 200km/h: 9.1sec (8.9sec on optional Corsa tyres).
Standing quarter-mile: 10.9sec at 216km/h.
Standing kilometre: 19.6sec at 272km/h
Top speed: 330km/h.
100 - 0km/h: 30.5 metres.
Dick Glover, technical director at McLaren Automotive, explained how it was done: “The challenge for us was to set new performance benchmarks against our key competitors, some of the best sports cars the world has ever seen.
“In that respect, we work like a Formula One team, where you are constantly trying to improve performance not against fixed parameters, but to win against competitors who are also constantly developing and improving.”
The 12C development programme was conceived under the title “Project 11” in 2005, when McLaren decided to build the first “pure McLaren” road car. The team includes people with extensive experience in designing and developing successful McLaren Formula One and in the development and production of the Mercedes-Benz SLR McLaren.
The first concept prototype 12C's were built in 2007 to test aerodynamic, powertrain, drivetrain and chassis configuration proposals, followed by more than 50 experimental prototypes and validation prototypes, which were tested in every regional market where the car will be sold, including Bahrain and Nevada in summer, and the Arctic in winter. Production prototypes are now entering a long-distance, real-world durability phase of 80 000km.
Head of testing Geoff Grose said: “Our teams have tested 12C prototypes in Sweden for cold weather programmes, Bahrain in summer dust storms, Arizona at temperatures above 45 degrees, South Africa for high-altitude testing and endless circuit and road testing in Europe.
“We've set up bases at Idiada in northern Spain and the Prototipo facility near Nardo in Italy where we run 24-hour sessions, as well as 18-hour sessions from 8am to 2am the next day. The remaining six hours allow time for a team to service and implement development changes ready for the next day's testing to begin without interruption.”
The 12C's M838T engine is a 3.8-litre twin turbo V8, designed by McLaren; it weighs only 199kg, and has dry-sump lubrication and a flat-plane crankshaft, so it can be mounted low in the chassis, lowering the car's centre of gravity and optimising handling.
High-level exhaust pipes exit from a mixing box rather than a conventional silencer unit, saving weight. An optional sport exhaust system made from Inconel, an extremely heat-resistant nickel-chromium-based alloy, further reduces weight and enhances the exhaust note.
Powertrain manager Richard Farquhar explained: “The decision to build a turbocharged engine for the 12C was taken early in the programme. We wanted low weight, bottom-end tractability, potent mid-range performance and extensive high-rev reach.”
It drives through a seven-speed, dual-clutch transmission, which can be switched through three different settings: Normal, Sport and Track, operated by finger-tip controls on a rocker behind the steering wheel: upshifts are by either pulling with the right hand or pushing with the left, and vice versa to downshift.
If the driver enters a sharp corner too quickly, requiring a strong braking action, there is every chance he will not be in the best gear for smooth acceleration out of the corner. If the left-shift control is depressed and held, instead of “clicked”, while under braking, the transmission matches engine speed to the correct lowest gear.
Also available are Automatic mode, Launch Control and Winter modes, the latter changing all electronic functions to suit low-grip conditions and delivering maximum driver aid and support.
The suspension is based on double wishbones with coil springs. The dampers are interconnected hydraulically and linked to a gas-filled remote reservoir. It has driver-adjustable roll control instead of traditional mechanical anti-roll bars, maintaining precise roll control under heavy cornering while decoupling the suspension in a straight line for excellent compliance.
The principle is simple physics: dampers featuring an hydraulic system of high and low pressure valves are interconnected left to right, front to back. When high pressure meets high pressure under roll conditions, stiffness results; when high pressure meets low under heave and warp, there is more “give” and comfort prevails.
As with the transmission, but independent from it, the driver can select Normal, Sport or Track settings for the suspension, modulating roll control system pressure, adaptive damping and electronic stability control settings.
The brake steer system applies braking forces to the inside rear wheel when the car is entering a corner too quickly to make the desired radius - supporting either a driver who has misjudged the corner, or a skilled driver seeking the fastest possible entry and exit from a corner.
Under normal circumstances the car would tend towards understeer but brake steer makes it behave more neutrally, bringing its nose back on line by assessing the steering angle to determine the driver's intended course and applying the inside rear brake to increase yaw rate and resume the desired course.
The system also works on acceleration out of a corner when the inside rear wheel has a tendency to spin, allowing the driver to put power down more quickly.
The chassis is produced in one piece by a resin transfer moulding process, which begins with loading dry carbon-fibre into a complex 35-ton steel tool before it is pressed together, heated and injected with epoxy resin.
Using a steel tool is new to the manufacturing process: usually carbon-fibre moulding is done in “soft” composite moulds. The subsequent post-curing process hardens the resin, and the chassis then enters a booth where key surfaces are machined with great precision in preparation for assembly.
The carbon-fibre chassis of the McLaren F1 is produced manually and takes as much as 3000 hours to complete each unit. The bonded carbon chassis of the SLR reduced that to about 300hours - but the new process developed for the 12C takes only four hours each.
SPECIFICATIONS
Drivetrain: Longitudinal mid-engine, rear-wheel drive.
Engine: 3799cc, twin-turbo, all-aluminium V8.
Valvetrain: 32-valve, DOHC, dual VVT.
Compression ratio: 8.7:1.
Redline: 8500rpm.
Transmission: Seven-speed semi-auto, dual-clutch.
Chassis: carbon-fibre monocell with aluminium front a rear sub-frames.
Length: 4507mm.
Width: 1909mm.
Height: 1199mm.
Wheelbase: 2670mm.
Track (F/R): 1656/1583mm.
Dry weight: 1301kg.
Weight distribution (F/R): 42.5/57.5 percent.
Brakes: Cast iron discs with forged aluminium hubs (F: 370mm / R: 350 mm)
Rims: 19 x 8.5J Front / 20 x 11J Rear.
Tyres: Pirelli PZero 235/35 R19 / 305/30 R20.
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