The McLaren 650S Spider becomes your favorite car—and hits 100mph—in 6.3 seconds

We test the McLaren 650S Spider. Cinematography by Ivan Flores, editing by Jennifer Hahn.

OK, we'll admit it—there was a lot of excitement in the office leading up to our time with the McLaren 650S Spider. And why not? This is a proper carbon fiber supercar, built in the same factory as one of the most successful and storied Formula 1 teams. It's from the same company that built the legendary McLaren F1, a 240mph three-seater that to many—including yours truly—remains the greatest car ever to turn a wheel. We were the first publication to get any time with McLaren's latest press car, fresh off a boat from the UK with a mere 350 miles on the digital odometer. The following few days were extremely memorable, and the Volcano Red convertible earned its position as our favorite car of 2015.

McLaren has been building road cars for more than 20 years now. We shan't bore you too much with talk of the F1, save to say it was the first completely carbon fiber road car, and it came with a fantastic 6L BMW V12 engine, three seats, and a top speed that wasn't equalled until the Bugatti Veyron appeared with another 400hp. Sadly, just over 100 were ever built (the plan was to make 300), and today you'll need quite a lot of money to buy one. Recently, one sold for $12 million—not bad for a car that was selling for less than list price in the late 1990s.

The F1 was followed by the McLaren Mercedes SLR, a joint venture with the company that supplied McLaren with its Formula 1 team engines for many years. A contemporary of the Ferrari Enzo and Carrera GT, the McMerc remains a little unloved, possibly thanks to the automatic gearbox and SL-like looks. The general feeling is that the car is less a McLaren than a Mercedes, which means it might be an under-appreciated bargain in the making should early 21st century supercars be your thing. But even if the design of the car suggested Stuttgart, it was in fact built in McLaren's state-of-the-art factory in Woking about 40 miles from London.

No such accusations could be leveled at the cars which have succeeded the SLR. McLaren uses a common platform for the different series of cars in its range, which use variations of the same carbon fiber chassis and turbocharged 3.8L V8. First out of the gates was the MP4-12C (later shortened to just 12C) in 2011. This was the first of the Super Series cars, and the 650S Spider is one of the latest evolutions in this series. (Above the Super Series is the Ultimate Series P1, and below is the new entry-level Sports Series 570S).

Design

The centerpiece of the Super Series chassis is called the MonoCell. The MonoCells are made for McLaren by an Austrian company called Mubea Carbo Tech through a process called resin transfer molding. This is much more automated than the almost-handmade "pre-preg" carbon fiber used in the F1 and SLR road cars or the racing team's Formula 1 cars, and in total it takes about four hours per tub. The MonoCell weighs just 165 lbs (75kg) yet gives the car its strength and stability. And because McLaren designed the MonoCell with coupes and convertibles in mind, the Spider loses none of the stiffness of a closed-roof car. What's more, the powered retractable roof only adds an extra 88 lbs (40kg) to the car's dry weight—3,020 lbs (1,370kg)—in relation to the 650S coupe.

Bonded to the MonoCell at the front and back are aluminum subframes onto which the engine and suspension are mounted. The body panels that cover all of this are mostly carbon fiber as well. On our test car, many of these were unpainted, showing off the pre-preg weave, which was beautifully aligned down the center of the front splitter and rear bumper (the unpainted carbon bits also save a few lbs here and there). The 650S' shape is an evolution of the 12C's, which came in for a little (undeserved in our opinion) criticism for being too anodyne.

As part of the redesign, McLaren now draws in a lot of elements from the P1. The front splitter is larger, as are the side intakes that feed the engine bay with cool air. McLaren say that the 650S has the same drag coefficient as the 12C (0.36, which is a little higher than most of its rivals), but the new shape produces much more downforce—24 percent more at 150mph (km/h) apparently. The car also features some active aerodynamics courtesy of the movable rear wing, which also pops up as an air brake when you need to slow down in a hurry.

The two-piece roof is electrically operated, stowing itself between the cabin and engine in 17 seconds at speeds of up to 30mph (km/h). Roof-up, the car looks very similar to the 650S coupe. With the roof down, the appearance from the side is more like a targa, thanks to the large buttresses behind each seat. These maintain the profile of the car and also double up as rollover protection.

One thing you do lose out on compared to the coupe is your view of the engine. Instead of a large rear window that exposes the engine bay to onlookers, much of the 650S Spider's engine is covered by the cubby into which the roof retracts. But what an engine it is, having now won its class in the International Engine of the Year competition three years running. It's a twin-turbocharged 3.8L V8, made from aluminum and designed from scratch for McLaren by British engineering firm Ricardo. Different versions of the M838T are used in all of McLaren's road cars—including a hybrid version in the P1—and surprisingly it's actually a relatively simple design.

There's no direct-injection for example, but it does have a dry sump (which keeps the height of the engine block down and prevents oil starvation during cornering) and a flat-plane crankshaft (meaning high revs and a high specific output compared to something like a short block V8). For the 650S, the engine got new pistons, cylinder heads, and exhaust valves. Throttle mapping and valve timing was also tweaked compared to the 12C, which helped drop CO2 emissions and sharpen throttle response. Forced-induction engines will always suffer in comparison to naturally aspirated ones when it comes to that last attribute, but the realities of climate change and 21st century emissions regulations mean turbochargers are becoming the norm.

The development of the engine from 12C to 650S also benefited from lessons learned on the P1. The goal, according to McLaren Director of Product Development Mark Vinnels, was to replicate the linear power delivery of the hybrid car (which fills in gaps in the torque curve with the electric motor). "We wanted to replicate this experience on the McLaren 650S as closely as possible," he told Ars. The new throttle mapping was designed "to give an instant feeling of response to any throttle input rather than a sudden boost of turbo torque. It’s more progressive. You also need to push the pedal less to get action."

The end result is an engine that revs freely to 8,500rpm, and you're encouraged to use those revs, too. Most turbocharged engines have relatively flat torque curves, so there's little point running them to the upper rev range, but the 650S' torque curve has been tuned to rise from 3,000rpm. The headline figures are 641hp (478kW or 650PS, hence the name)—at 7,250rpm, 500lb-ft (678Nm) at 6,000rpm. As is de rigueur these days, extremely clever electronics govern the car's behavior, with different modes for the powertrain and suspension (normal, sport, track, and winter), and they're independently selectable (so you can have the suspension in normal and the powertrain in track, for example).

That power gets channeled to the rear wheels through a seven-speed dual-clutch gearbox (Seamless Shift Gearbox or SSG in McLaren-speak). This has also evolved from the 12C, although the changes involved new code rather than mechanical bits. There's no limited slip differential, though. Instead, the car uses an open diff and a brake steer system, which the company originally developed for its 1997 MP4-12 Formula 1 car. That system—which was quickly banned—used a second brake pedal to brake the inside rear wheel in a corner.

That system was fine for Mika Hakkinen and David Coulthard, but two brake pedals might be a bit much for the rest of us. In the 650S, it's all handled by the computer that governs the car's suspension. The ProActive Chassis Control suspension on the 650S is rather interesting in its own right. There are double wishbones at all four corners, but it's the dampers where things start to get complicated.

It's not a magnetorheological system like the Corvette Z06 or Lamborghini Hurácan; instead McLaren uses twin-chamber hydraulic dampers (using the same fluid as the power steering and driven by the same electric pump). Each corner is independently controlled, and the bump damping is constantly varied based on road conditions via adjustable actuator valves. However, it's the hydraulic roll control where things get fascinating. Rather than use antiroll bars, the dampers are connected to each other (again similar to a system that was used in Formula 1 until it got banned).

The dampers' compression chambers are connected to the rebound chambers on the opposite side (so front-left compression to front-right rebound and so on), but the compression chambers on each side are also connected (front-left to rear-left, etc). With all four corners linked, the car exploits the fact that fluids will flow from high to low pressure. For example, when a car is cornering, weight transfer induces it to roll (in a right-hand bend the car will roll to the left), so the damper on the outside of the turn will compress as the inside damper extends. Since they're cross-linked here, they oppose each other, which controls the amount the car rolls.

Accumulators control the amount of hydraulic fluid flow from damper to damper. As the fluid enters the accumulator it meets a pocket of gas separated from it by a diaphragm, and it's this base pressure in the accumulator between the gas and fluid that determines how much roll stiffness there is. The pressure increases in each successive handling mode (normal, sport, track), with the highest base pressure and therefore the lowest possible roll in track. The end result is high roll stiffness, but low stiffness in other conditions (when the car is pitching forward under braking or backwards when accelerating), all at levels chosen by the driver.

What's it like to drive?

The practical upshot of all that technobabble and engineering talk is that the 650S is a revelation behind the wheel. Once you've swung up the dihedral door and climbed over the wide sill of the MonoCell, you find yourself sitting quite close to the centerline of the car—and just a few inches from your passenger. Pull the door shut and the seat whirrs forward on its motors, as does the steering wheel.

The wheel itself bucks the prevailing multifunction trend by not having a single button or switch on it (unless you count the horn). Its rim is just about the perfect width (see our P1 video for an insight into why), and the aluminum paddle shifters are well-placed. They're also a single unit—pull the right paddle toward you and the left moves back, and you could theoretically just use a single hand to change gear, pulling the right paddle to shift up or pushing it to shift down (that does mean the usual trick of pulling both paddles toward you to engage neutral doesn't work here).

The turn signals and windscreen wipers are controlled by conventional stalks (made from solid aluminum) with a second smaller pair for the infotainment system and car's settings (left) and cruise control (right). The instrument binnacle is dominated by an analogue rev counter, flanked on either side by a pair of small digital displays. The rest of the cabin is a minimalist exercise in carbon fiber. With such a narrow center console and such wide sills, the climate controls have been shifted to the doors.

That center console itself is dominated by the infotainment screen (in a portrait orientation), below which are the start button, the controls for the suspension and powertrain settings, launch control, the handbrake, roof, and so on. The biggest benefit of sitting so close to the center of the car is very good forward visibility, since the A-pillars of the windscreen are further off to each side.

Foot on the brake pedal (also beautifully machined from aluminum), a push of the start button, and the engine fires up. Pull the right paddle to select first gear and off you go. It's then, in those first few miles, that you begin to realize how good a job McLaren has done with the 650S. With everything set to normal and the gearbox shifting automatically, the car is docile and well-mannered. It soaks up the potholes of Washington's streets, riding with almost limo-like comfort. The throttle mapping means you've got a good amount of travel before all 641 horses come to say hello, making it very manageable in traffic.

Decoupling the suspension and powertrain settings was a smart move by McLaren. For much of our time with the car, we kept the suspension in normal mode, switching the powertrain to sport, which also added a nice aural dimension by flaring the exhaust on upshifts (by cutting the spark and then igniting the fuel as the exhaust valves open). As we didn't have an opportunity to track the car, we can't comment on its handling at or close to the limit; suffice to say that at anything close to legal speeds, you're barely scratching the surface.

The electronics that control the chassis and engine work with you, allowing more wheelspin and greater slip angles as you move from sport to track. The steering—thankfully a hydraulic power-assisted system as opposed to the electric variable-ratio kind—communicates what the front tires are doing. Those tires are bespoke Pirelli P Zero Corsas, and once warm they offer plenty of grip. As such, it's a car that rapidly inspires confidence.

At the same time, more than 600hp and rear-wheel drive mean the car demands some respect (just like the Z06). With such little mass and such a good power-to-weight ratio, it can be extremely fast. Actually, scratch that. The 650S' acceleration is just bonkers. Yes, it's even faster than a Tesla Model S P90D in Ludicrous mode, which might keep up with the McLaren from zero to 60, thanks to all-wheel drive and the instantaneous torque from its electric motors (although Road and Track got the 650S to 60mph in 2.7 seconds) but after that the McLaren just disappears. From a standstill, 100mph is just 6.3 seconds away, and it keeps going until finally running out of steam on the far side of 200mph. Thankfully, the carbon ceramic brakes and the airfoil are more than up to the task of bringing things back down to Earth.

What's it like to live with?

When McLaren announced the 12C back in 2009, one of its messages was that this would be a supercar that you could drive every day if you wanted to. And even though the 650S has upped the drama quotient over that car, it's kept that practicality—within reason. The wide sills make getting in and out a little bit of a chore, even if the seat moves back and the steering wheel up and out of the way to aid you. The forthcoming 570S has a modified MonoCell that makes this much easier. Once ensconced in the car, the good ergonomics and view make up for that, as do the comfortable and supportive seats.

With the roof up, it's also quite refined—certainly more so than the Lamborghini, in large part due to the turbocharged engine. Roof down, the car sounds more dramatic, and the heated seats and climate control are good enough that even on chilly mornings you find yourself dropping the top. The trunk (or frunk, if you will) is capacious for a mid-engined car, easily swallowing our videographer's gear for the day (you could fit at least one Ron Amadeo in there, too). There's more storage behind the cabin with the roof up, although in the cabin you're limited to a small cubby between the seats. There's no glovebox, but it does have a pair of cup holders located underneath the center console, which is slightly awkward but not an impediment to a late night McDonald's run. Speaking of late nights, we did find the headlights were a little underpowered when dipped, as they wouldn't illuminate far enough down the road. No such worries with the full beams, though.

McLaren's Android-based infotainment system—called IRIS—is not bad. The first 12Cs were delivered without a working infotainment system, which was a bit of a PR disaster. Thankfully the intervening years have given the system time to mature. The portrait screen is a great touch, and you can swipe and pinch things as well as use the buttons and jog wheel to control it. Smartphones connect easily via USB or BlueTooth, and the Meridian surround sound system was pleasant to our non-audiophile ears, coping well even with the roof down. The navigation app wasn't very intuitive, it must be said; at one point it took us more than 10 minutes to cancel out an address that IRIS decided we wanted directions for.

Forward visibility is, as we mentioned, excellent. The view out the back is better than you'd get in a Hurácan, and those high buttresses don't create blind spots as badly as you might imagine. The rear-view camera is less than amazing, though—it definitely suffers from IRIS' portrait orientation.