The McLaren Speedtail is an astonishing accomplishment, a truly luxurious road car that could presumably be driven from Chicago to Bonneville, run on the salt, qualify for the 200-MPH Club, then motor on to San Francisco—all in the same state of tune and on the same Pirelli tires. That’s not just impressive. It’s almost miraculous—and entirely believable.
Of course, there is one critical thing that will prevent such an adventure from occurring: The Speedtail’s reasonable but unorthodox three-seat configuration precludes it from being sold here for anything but exhibition purposes. Still, Americans have already secured many of the 106 examples McLaren plans to build from 2020 onward, so perhaps we’ll see one someday. If you ever do, you’ll likely never forget the occasion. It’s a memorably spectacular car, with most of its forms inspired by human, animal, and piscine morphology. (Read more with McLaren’s design director, Rob Melville.)
At the same time, this is a highly technical vehicle, featuring complex internal ducting for various streams of air flowing into and through the body. One of the cleverest aerodynamic tricks is covering the exposed front wheels so that air is not ejected sideways but is instead captured and directed along the body—inside and out. I find the visual contrast between the covered front wheels and the bare casting of the rear ones slightly shocking. The effect is a bit like seeing a badly maintained beater with one of its plastic wheel covers off. If I were to suddenly have funding for a Speedtail (and were one available), I’d attach a plain, thin disc to the rear wheel rim, rotating with the wheel—no ducting as there is in front, just a fairing.
But that’s the only thing I might want to change, given that the total composition is so well balanced and cohesive. McLaren published no drag coefficient figures, but the number must be quite low for the car to be able to attain the Speedtail’s anticipated 250-mph top speed. The key to that capability lies in the extended rear body with its long overhang. Forty-six years ago, I worked on a little city car in a wind tunnel. As an exercise, I appended a smoothly tapered 6-foot tail on the specified 11-foot body and ran a series of tests, chopping off 6 inches or so for each successive run. With that ridiculous appendage, the Cd was around 0.16. With each cut, the coefficient rose, and when I got back to the specified length, I’d managed to achieve a 0.203 Cd, exceptional for so small a car. So body length really matters a lot, aesthetically and technically.
1. What you can’t see here, because it’s fitted so tightly, is the left-hand aileron that has no turbulence-inducing, leading-edge surface break. It and the symmetrically opposite aileron only shed vortices at their outer corners.
2. A dramatic rib with concave surfaces on both sides rises from the roof bubble’s sill line at the back of the door.
3. Induction air for the engine comes from this flush duct on the back of the roof, split by the long, elegant CHMSL.
4. The longest single line on the Speedtail, this curve defines the character of the total form.
5. The upper bubble flattens a bit and allows the door glass to be more vertical than it would be in a true raindrop shape.
6. Air is channeled into the main radiators just behind the doors in the body flanks.
7. The aperture at the base of the windshield insulates the wiper and mechanism from the oncoming airflow. It’s not a new idea, but it’s always an excellent one.
8. The front fender form is hard toward the rear and softer, flatter, and wider toward the front.
9. Rear-vision cameras are mounted far forward in the doors, protrude when the engine is running, and retract when the car is in Velocity mode, when the body lowers by 1.4 inches on the suspension.
10. Air from the low-temperature radiators in the front is extracted through these vents in the doors.
11. The car pinches inward at about half the wheelbase, but a strong, crisp horizontal line runs the entire length between front and rear wheelhouses
12. A fine piece of surface work, this hard line disappears into the surface just before the wheel opening but links visually with the disappearing line from the upper edge of the side air outlet.
13. There’s a huge mass of extremely hot air behind the passenger compartment. Most of it is extracted at the rear, and these tall finlike panels direct it slightly inward
to reduce the wake signature.
14. A carbon-fiber diffuser molding at the bottom of the rear body provides downforce, which is modulated as required for stability in fast running and under braking.
15. For once on a supercar, a sensible license plate mounting area is provided without it being an eyesore, thankfully.
1. Flowing outward and upward from the center of the nose, the surface folds over to establish a muscular front fender profile.
2. The tail of the lower front fin sweeps around the corner with a sharply defined horizontal break line.
3. The carbon-fiber baseplate emphasizes the horizontality of the lower part of the Speedtail.
4. I particularly like this little triangular inset section between the hard line along the sill and the disappearing edge of the frontal air outlet, all beautifully modeled.
5. The retracted rearview camera lens cover is shaped to repeat the whole body side profile and serves to initiate the superb sweeping rear fender profile line.
1. It’s very subtle, but the last part of the upper tail turns up just a bit from the downward-sloping surface of the rear body.
2. This curve, starting at the aperture for the retracting rear-view camera, is a splendid gestural sweep that evokes long, muscular shapes in felines or humans.
3. The upper part of the windshield is electrochromic glass that can darken electronically, thereby eliminating the clumsiness (and weight) of sun visors.
4. The near half-round curve of the windshield baseline in plan view is even more extreme than that of the Lancia Stratos, thanks to the central positioning of the Speedtail driver.
5. Slim headlamps are tucked under the upper lip of the front corner inlets, considerably smaller than those of McLaren’s 570S, just vertical slots at the outer edges.
6. Yes, there is a front lid for access to one of the luggage spaces.
7. Very slightly pointed, the nose is almost exactly a half circle in plan view so the whole front end mimics a modulated drop of water, with only a little more fluid dynamic resistance than that ideal shape.
8. The carbon-fiber baseplate has a slight plan-view joggle where fins below the side air inlets move outward from the base circle.
9. A vertical splitter fin joins the baseplate and the painted body section, diverting incoming air toward the lower outer brake cooling inlets.
10. This anhedral fin gives some side-view substance to the painted part of the body and directs air toward the static surface of the front wheels …
11. … which clash visually with the uncovered 21-inch, 10-spoke forged rear wheels, handsome as they are. And a few ounces are saved.
12. From its thinnest depth at about the middle of the doors, the painted skin swells downward to fair the rear tires.
1. The left-hand rearview screen is directed to the driver’s eye point.
2. Swirling panels of lightweight leather and “Titanium Deposition” carbon fiber, not to mention “Thin-Ply Technology” carbon fiber (McLaren’s capitalization) highlight the central driving position and focus the driver’s vision toward infinity. Is that too dramatic? Probably not.
3. Maybe this means 200 kilometers per hour, only half the available top speed.
4. Twin screens cover all areas behind. Like a truck, there’s no backlight.
5. You still have to be able to pay tolls today, so these small opening windows are necessary, but one day that, too, will be all electronic.
6. The driver’s throne is a handsome thin-structure piece. The leather is textured to make it easy to slide in from either side but also to hold you in place while driving hard.
7. At first glance, the two passenger seats are hard, thin slabs. But we guess they’re very comfortable, and each probably costs more than your daily driver.
8. Believe it or not, specially prepared lightweight leather serves as floor covering.
9. This textured panel provides a passenger footrest.
The perforated engine cover allows heat to escape when the car is stationary. It’s configured to accommodate both the long, linear CHMSL and the induction air inlet about halfway down the back curve of the modified bubble roof, all transparent surfaces of which are glass, much of it able to be tinted electronically. Windshield and door glass are always transparent, of course.
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