The McLaren MP4-12C needed only 100 yards to make clear that it won’t play by Enzo’s supercar rules. Pain is not part of the deal. Bumps don’t jangle its nerves. The engine and transmission do their business without a fuss. We expected the MP4 to be quick and track-hungry, but the baby-carriage ride we noted with the “normal” chassis mode—engaged for the scarred and tarred paths in Mexilhoeira Grande, Portugal, where McLaren presented the fruits of its seven-year labor—rang our “holy cow!” bell.
You spring open the MP4’s dramatic insect-wing door by sweeping a hand along a flush surface tucked under the side scoop’s upper edge. Leading with your right leg followed by a dab of body English, it’s an easy glide into the nicely bolstered seat. There’s a huge 9000-rpm tach and a steering wheel unburdened by switchgear, with a center-pivoting shift paddle. The leather and faux suede are sewn to Savile Row standards.
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The most impressive part of the cockpit is the intelligently arranged center console. There’s a big red button to fire the engine, one knob to set handling parameters, a second knob to adjust powertrain behavior, and five logically positioned single-function buttons. The less critical controls are positioned out of the action zone on column stalks, along the armrests, and on the dash below the instrument cluster.
Punching the hot button with the brake pedal depressed cues genteel whirring sounds behind your shoulders. Blipping the throttle in neutral conjures no Formula 1 starting-grid fantasies. This V-8 is soft-spoken, polite to a fault. Its initial impression is unimpressive. And with no clutch pedal or shift lever to play with, there’s risk of Lexus-like sensory deprivation setting in.
Tugging the right side of the shift paddle engages first gear. The dual-clutch box delivers such a clunk- and chug-free roll-off, you’d swear there’s a torque converter at work here. Under light throttle, automatic upshifts are smoothly and swiftly executed. Before you realize it, the digital gear indicator has counted up to six and you’re rolling along at highway velocity with minimal enthusiasm from the tach needle or the engine room. The MP4’s unspoken mantra is speed without the spectacle.
Fortunately, politeness is just one aspect of the MP4’s psyche. The “normal” drive mode—the pride of the development team and as heretical to the supercar cult as the Lamborghini Miura’s mid-engine move was 45 years ago—is merely the appetizer to McLaren’s feast. So, after paying our respects at normal, we moved on through the sport and track settings to liberate the MP4’s mischievous twin.
With a 4000-rpm spread between torque and horsepower peaks and 17.4 psi of boost on tap, the MP4’s 3.8-liter engine feels more like a strapping V-10 than a mini V-8. There’s no hint of turbo lag or, for that matter, any evidence that this engine is turbocharged except for an occasional waste-gate chortle during shifts. The torque curve is as flat as an electric motor’s.
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Lock the throttles open long enough to visit the top half of the rpm range, and three things happen: The intake plenum is jammed with excess air, a valve inside that box switches to a racier setting, and gentility is blown out the pipes. Without rivaling the shriek of a Ferrari V-8 or the gusto of a Lamborghini V-10, the MP4 rouses the hoofbeat of 593 horses keen on crashing the corral gate.
McLaren’s math says that the MP4’s broad torque curve and 5.4 pounds per horsepower will trounce Ferrari’s 458 Italia on the run to 60 mph (in three seconds flat) and through the quarter-mile (less than 11 seconds). We’ll check that prediction in the inevitable fight-to-the-death comparison test, but for now our drive was limited to a few blasts to 150 mph on the auto-estrada and a dozen or so chaperoned laps around the curve-crammed, 2.9-mile Autódromo Internacional do Algarve.
The MP4 checks the crucial speediness and joy-ride boxes. It’s quick and decisive when whipped and clever enough to flatter its driver. Turn-in is crisp, and the cornering attitude is readily adjustable. If you charge a bend with excess speed, the MP4 automatically dabs its inside rear brake to mitigate the understeer you provoked. Add throttle prematurely exiting a turn, and the tail will step wide but never in a threatening manner because the stability-control system engages unobtrusively to save the day. Amateurs will enjoy this ride, good drivers will feel like track stars, and great pilots will find the MP4 a handy tool for polishing their skills. There’s something here for everybody.
The MP4 has two special weapons found in no other supercar. Its hydraulic suspension so inhibits body roll that it handles tight jinks with a go-kart’s agility. And the rear airfoil, which springs to attention during hard braking, adds yards to every straightaway.
The MP4 has the moves of a master and the brains of a child prodigy. It verges close enough to perfect that Ferrari will feel the heat of a serious competitor while other supercar makers will struggle to match this combination of value, performance, and technological intrigue.
Of course, there are lapses. The MP4 suffers from an obvious lack of sex appeal, and it was christened with a part number instead of an evocative name. We wouldn’t mind a touch more steering feel and less brake-pedal travel during aggressive stops. High-speed stability is slightly shaky, a fault probably attributable to the substantial aero forces heaving on the rear of the car. Lower seat bolsters are spread to accommodate thunder thighs, a flaw easily resolved by ordering the optional sport seats. A lighter, louder sport exhaust system is also coming. Lastly, the MP4 could use a nicer welcome mat than the mouse fur covering the doorsills.
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However, the MP4 earns A’s for inspiration and execution. Early adopters have dibs on the 300 or so cars planned for U.S. delivery this year (beginning in August), but they’ll be followed by 1000 or more cars in 2012. And where the MP4 goes, other McLarens will follow. Count on a convertible, a less-expensive model, and a successor to the legendary McLaren F1 before the clock strikes 2016.
If there’s a ray of sunshine beaming down on a usually gloomy Great Britain, it may be Bruce McLaren smiling over what his successors have achieved.
Ray Harroun initiated the trickledown trend a century ago at the first Indy 500 by using a rearview mirror instead of a riding mechanic to spot traffic. Harroun’s victory drew attention to his innovation, and mirrors were quickly installed on road cars. That first track-to-street tech transfer became the tidal wave of overhead cams, disc brakes, and aero aids we now take for granted.
McLaren Automotive used the same strategy on the MP4-12C. It is not so much a newbie sports car as a showcase of speed secrets learned in half a century of racing.
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Early in this project, McLaren engineering director Neil Hannemann nominated an engine for the MP4-12C that was originally developed in Nissan’s racing department. Nissan and Infiniti had raced this spinoff from the Infiniti Q45 V-8 at Le Mans (1997 and 1999) and in two Indy Racing League series (1997–2005).
Other than a 93-mm (3.66 inches) bore dimension, little of Nissan’s VRH engine exists in today’s M838T V-8. Developed in collaboration with Ricardo, this is a compact 90-degree twin-turbo V-8 with aluminum construction, Nikasil bore surfaces, dual overhead cams, and variable intake- and exhaust-valve timing. The modest 3.8-liter displacement is McLaren’s nod to the environment.A flat-plane crankshaft evens the spacing of exhaust pulses feeding each Mitsubishi turbocharger. Maximum boost is 17.4 psi. Dry-sump lubrication allows the engine to be mounted low. The cam covers and the intake manifold are molded in composite plastic to save weight. Fuel is delivered by a port-injection system. With an 8500-rpm redline and a 593-hp peak at 7000 rpm, this engine is a screamer, though some of the audio entertainment is lost in the turbos. The exhaust pipes are routed high to clear space for a large rear diffuser.
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Porsche’s 962C pioneered a path to dual-clutch transmissions with five endurance-racing victories in 1986 and 1987. The attraction, then and now, was avoiding loss of turbo boost during upshifts, though dual-clutch technology is not currently allowed at Le Mans or in Formula 1.
Graziano, a long-standing supplier of automated manual transmissions to the sports-car stars but new to the dual-clutch game, manufactures what McLaren calls its Seamless Shift Gearbox (SSG). In addition to two wet clutches and seven forward speeds, SSG has a “pre-cog” feature; applying light pressure to one side of the shift paddle alerts the transmission’s electronic controller whether the next gearchange will be an upshift or a downshift, thereby expediting the transmission’s response to the driver’s prerogatives.
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Thirty years ago, McLaren’s MP4/1 toppled the Formula 1 apple cart with the first carbon-fiber monocoque. In 1993, that technology trickled down to the company’s F1 supercar. Gordon Murray, the firm’s technical director until 2006, recalls carbon fiber’s progress in this issue, saying a tub that used to cost $100,000 20 years ago is now down to about $10,000.
Cutting cost by a factor of 10 is trickledown in its purest form. The MP4-12C’s 165-pound monocell tub is manufactured by the Austrian firm Carbo Tech Composites using a resin-transfer molding process. The company loads dry, preformed carbon-fiber material into the mold along with the aluminum inserts used to attach the doors, roof, and structural components to the monocell. Inflatable bladders are likely used to create the tub’s hollow sections. After the seven-segment steel mold is closed and clamped in a press, the carbon fibers get an injection of fast-curing epoxy resin. Post molding, the monocell’s metal interfaces are trimmed in a computer-controlled milling machine to ensure high dimensional accuracy.An aluminum space frame supports the powertrain and the rear suspension. At the front, sacrificial aluminum tubes take the brunt of a forward collision. The MP4-12C’s seat frames and dash structure are magnesium die castings. The aluminum windshield frame is reinforced with a boron-steel tube. The front fenders, the hood, and the roof are stamped aluminum, while the remaining exterior components are fiberglass.
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The MP4-12C’s clever suspension bits worked so well in Sébastien Loeb’s Citroën rally car that the FIA banned this technology in 2006. What looks like an ordinary shock absorber at each wheel is instead a hydraulic cylinder. In relation to wheel motion, a piston inside each cylinder pumps hydraulic fluid into and out of the chambers above and below the piston. All eight chambers are connected to two accumulators, each of which contains fluid and nitrogen separated by a bladder.
Unlike conventional shock absorbers, these pistons have no orifices or valves. Instead, the flow restrictors are located where the hydraulic lines attach to each cylinder. The size of the restriction, which is varied by an electronic controller, determines the amount of damping provided.
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| Hydraulic lines connect the four wheel cylinders to two accumulators. |
The pressurized nitrogen contained within the two accumulators acts as a spring to resist roll motion; each accumulator handles one cornering direction. Individual wheel motion is resisted by the coil springs.
This technology saves the weight and complexity of conventional anti-roll bars, but more significantly, it’s a boon to tuning. Soft springs and gentle damping provide a pleasant ride. A high accumulator spring rate assures minimal body roll, which is further diminished by adding more fluid to each accumulator. When the driver turns a cockpit knob from the normal setting to sport or track mode, an electric pump adds the appropriate amount of hydraulic fluid. (Infiniti and Toyota also use versions of this Tenneco Kinetic system.)
Key MP4-12C suspension components (control arms in front, multilink in back) are forged aluminum. There’s an Eibach coil spring at each corner. Pirelli P Zero and P Zero Corsa tires are available, and the MP4-12C offers two brake systems. The standard stoppers supplied by AP Racing (a Brembo subsidiary) use two-piece iron and forged aluminum rotors. Those with track-day aspirations will be better served by the optional Brembo carbon-ceramic system.
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Movable aerodynamic devices come and go in Formula 1. That didn’t hinder McLaren from fitting the MP4-12C with a rear wing that lifts to 32 degrees for enhanced downforce or 69 degrees to act as an air brake. The airfoil, initially deployed by a small hydraulic cylinder, uses wind pressure to reach its maximum height. To help handle the substantial downward forces generated by the wing and the underbody diffuser, the rear coil springs are supplemented by what McLaren calls a heave spring; this device resembles an anti-roll bar with one reversed arm (formed into a Z-shape rather than a “U”). View Photo Gallery
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