Speed Week: McLaren P1 vs Porsche 918

The McLaren P1 and the Porsche 918 Spyder. Despite the very obvious talents arrayed on this peculiar little strip of Spanish tarmac, these are the two cars that drag the word ‘exceptional' into deeper and darker linguistic territory. Hyperbole can be a dangerous thing, but in this case, it's entirely justified. With a combined value of more than 1.5-million quid and possessed of enough horsepower to spin Europe on a pivot around central Germany, they have so much cutting-edge, hybrid technology stuffed into their actively aerodynamic fuselages - feels a bit banal to call them simply ‘bodies' - that they leak the future from their Inconel exhausts. What we're looking at is the distillation of the intellectual might of fast-car super boffins. Today, they face off for the first time on the same day, on the same track. To be blunt, I can feel the familiar itchy prickle of nerves.

Photography: John Wycherley and Rowan Horncastle

One reason is that these two draw attention like barracuda in a fishtank, so any screw-ups will be very public and, not incidentally, cripplingly expensive. The second reason for my reticence is that the last time I drove a McLaren P1, it tried to spit me off a wet European motorway at 80mph, in what could have been one of the shortest and most embarrassing road tests in history. In a triumph of survival reflexes over skill, it took two lanes to gather it back up, and then stony silence for 20 minutes as editor-in-chief Turner - who was unfortunately in the passenger seat at the time - stared blankly at the carbon dashboard and monotonously repeated the word "No." Luckily, with the after-effects of post-traumatic stress disorder, he's blanked the episode from his mind. Although he does still flinch if I mention Belgium.

Unfortunately, deciding which to drive first is like choosing a pistol for a light-hearted game of Russian roulette. Concerted staring must be employed, just to get the measure of the two. Equally unfortunately, the 918... looks a bit daft. A white car with giant threes plastered down the sides and bonnet, and vinyl red scallops splashing backwards from the headlights, like mascara applied at 100mph. Porsche's most advanced and psychotically fast production car probably doesn't need the look-at-me warpaint. But ignore the fripperies and with the contrasting carbon roof panels, black spoilers and industrial rear section, the 918 cuts a mean stance. The dwarf exhausts periscope up from the centre of the naturally aspirated 4.6-litre V8's vee to exit through the car's thorax, and there's a table-top of a wing currently berthed flush against the rear body.

This one also features the Weissach performance package - an option which deletes 41kg through the use of magnesium wheels, ceramic bearings, a lack of carpets and trim and other weight-saving measures. A keener edge to an already razor-sharp car. You can't see the pair of electric motors that create the Porsche's four-wheel drive - one wedged between the seven-speed PDK 'box and the petrol engine, and the other just aft of the front boot - but they are definitely there. In the metal, it's a special thing, no doubt, but a friendly- looking hypercar. If such a thing exists.

The P1 is a different story. It just looks plain evil. Painted black-hole purple, it appears physically smaller than the 918, more menacing. There's not a spare ounce of fat. And every strake and swoop has an aero function, from the teardop of the driver's canopy to the bonnet vents that push hot air up and away from the radiators and yet leave a specific channel of cold induction for the engine's roof snorkel. There's only one 26kg electric motor here, this time downstream of a turbocharged 3.8-litre V8 and pushing through a similar SSG seven-speed paddleshift. And, yes, it drives only the rear wheels. Like the 918, the expanded horseshoe of a rear wing is currently in the down position. It won't stay that way for long. Mainly because it's time for me to see whether the fastest McLaren is as much of a handful as I remember from that trip back from Spa.

Slip into the driving seat, and you're surrounded by the matte finish of the carbon MonoCage - essentially a vaulted version of the 650S's MonoCell for even more intense rigidity - and faced with a remarkably even view. You really can see out of the P1, and getting comfortable takes no time at all. A quick press of the starter button, and the turbo V8 fires with a raw bellow, before settling into an even, racecar high idle. Press ‘D' on the centre console, and we burble gently out of the pitlane, feeling every single eye.

Here's a thing: at half throttle, the P1 is very easy to drive. You can position it, the steering is light, the delivery smooth. There's a defined kick when the turbos come on song, and, yes, it's incredibly fast, even when you're not really pushing, but there's a sense that it all works, and if you've ever driven a baby-brother 12C/650S, the essential experience is familiar. After a few laps, I pause, and push the requisite buttons to get the P1 into the track-only Race mode, which takes 30 seconds. In Race, the rear wing deploys to full 300mm extension, the ride height drops by 50mm and the spring rates increase by 300 per cent. The hydro-pneumatic RaceActive Chassis Control suspension also starts to more aggressively manage roll-control, heave and damping, and the wing, venturi and active flaps just ahead of the front wheels combine to produce roughly 600kg of downforce at 160mph. If you're carrying enough speed, it feels lashed to the floor with steel hawsers.

We do a full-boost acceleration run. It's even more insane than I remember. Left foot on brake, throttle, wait for the boost to reach peak, and then simply lift the left foot and plant the right. Not a complicated dance, but the side effects may include vomiting. The launch causes my ears to make a soft clapping noise as they meet somewhere at the back of my head. It's not just fast, it's extraordinary, a violent rent in the atmosphere that means the P1 is there, and then just... not. And it's worth noting that it's not perfect: there is wheelspin in second, and all of the first three gears leave black, greasy lines along the tarmac. Our own figures reveal 0-60mph in 2.7secs, 100mph in five dead. Brutally fast. But also wise to remember that the standing-start party trick is only part of the story, and I lean back into the seat and progressively apply more throttle. And then full throttle.

Castellolí suddenly becomes instantly, terrifyingly small.

The P1 devours the straights and rips through the corners. It makes a noise like a Harrier jump jet trying to land on the back of your head, and on full-throttle changes, the cymbal crash of the dump valve behind your right ear is enough to make you flinch. It feels light, spiky and nervous, and edits the circuit into a series of places to breathe. Every gear brings a revelation, mainly the one that I'm constantly half a step behind the car: it feels murderously fast, and if you get it even minutely wrong (such as turning in even slightly on the brakes), disconcertingly loose and vehemently rear-wheel drive. For the first couple of laps at proper full-throttle speeds, I'm not sure I even blinked. The back straight is managing somewhere near 150mph, and I'm well into the ABS by the end of it. I haven't dared look down at the speedo on the main straight. Adrenaline? I can feel my heartbeat in my eyes, and I'm surprised I haven't shattered my teeth I'm grinning so hard.

The 918 cannot possibly be this fast.

Back to the pits, and half an hour to calm down and familiarise myself with the 918's interior. Now this is a different kettle of carbon fibre. A giant glassy touchscreen of a central spine, familiar Porsche cues, but twisted into new and interesting forms. It's comfy too, with similar ergonomic excellence to the McLaren - these are not particularly compromised machines. The Porsche feels bigger, though, and in the first couple of warm-up laps, noticeably heavier - it is, by more than 200kg - though the weight is carried low. Again, it's very easy to drive, but that naturally aspirated motor sounds pure racecar, and the experience and feel are immediately totally different from those of the P1.

No surprise, really. No turbos, more volts. The 918 has an engine vaguely related to the Le Mans-winning RS Spyder motor with aluminium block and heads, a flat crank and a 90-degree vee, supplemented by those electric motors for each axle to give instant AWD. When you get the motor singing to the 9,150rpm red line, it sounds like it's splitting atoms in your wake. Soon enough, we dispatch Sport and reach for Race mode. The rear wing raises to the attack position from its hideaway, and the 918 prepares for launch.

For a little while, I run out of words. It's quicker than the P1. From a standing start, I've only driven drag cars that feel like this. Pure grip, no wheelspin, ballistic thrust. The way the 'box snatches gears is like a striking snake, quicker than you can think. And the way the 918 puts on speed like a particularly unrealistic computer game. It might be heavier than the McLaren, but at this point, it feels like every ounce of its specific gravity is dedicated to traction. Our timing gear suggests it hit 60mph in a barely credible 2.5secs, a similar five to 100. But it feels faster. More incredible than that, it feels easy.

And that's when it all goes a bit weird. The Porsche 918 is different gravy to the P1, because where the McLaren shreds your nerve endings and heightens your impression of speed, the 918 is much, much easier to drive at the kind of pace usually only experienced by far more talented people. The impression of fully lit aerodynamics is less pronounced, but the traction through corners simply cannot be denied. The all-wheel drive fills in the holes in your talent, mops up, lends a helping hand in situations where the P1 feels like it wants to bite everything off.

An example. Manage the long left-hander onto the back straight correctly, patiently, and you can fire down ferrying afterburner speed. The P1 loads like a thing possessed, the aero pushing the car into the floor, even at relatively modest speed. Except that I was carrying a little too much speed at the start of the corner. I felt the already-light steering lose tension and the nose start to slip wide. And, at somewhere north of 80mph, I did the worst possible thing and lifted off the throttle. The P1 yawed, then snapped sideways like a racing car, the downforce generated by the rear wing immediately eliminated by the slight rotation. We barely skimmed the exit kerb, and all I could think about was one wet morning just outside Brussels, and my monotonous boss.

The same corner in the 918, and things couldn't have been more different. I loaded the car up and tried taking it at 70mph. Rock steady. Then 80mph. Then 85 and 90. Then I tried lifting, exactly like the P1. A bare shimmy and a tug from the front, and that's it. I eventually ended up managing the corner at 95-ish, and couldn't face heading in any faster. And yet the 918 is anything but boring. There's glorious feedback through the steering and, though not as hysterical as the P1, the chat is more comforting. There's almost as much power as the McLaren, but it arrives in less of a heady, all-consuming headrush. There's less to manage, but plenty to be getting on with. Its just as fast, but not the same.

The figures suggest that these two are equally as fast around a track. With me driving, and with the Porsche being a more flattering thing to pilot, I'm quicker in the 918. But every time I drive the P1, I understand it a little more, start to be able to manage its furious delivery, and the gap starts closing. Honestly? The speeds are getting to the point where a miniscule misstep is going to leave a gaping hole in the perimeter wall. The truth is that these two cars are occupying a space so far above what we currently accept from a performance car that they are desperately hard to assess in just a couple of days. Which means we need more time. And more miles. Which is rather handy, because, for once, that's exactly what we've got.