2015 Porsche 918 Spyder First Test
Fire and Ice: They Don't Build Supercars Like This Every Day
I glance to my right at the guy driving the Volt and do a double take -- why is he grinning and videoing the Porsche 918 with his iPhone like that? Ah, yes. Of course. The 918 I'm in is whispering along in its EV mode right now, which makes he and I sort of like EV buddies! I give him a big thumbs-up, a friendly gesture of geek communion, and then whoosh the Porsche ahead in traffic. A few minutes later, a café racer shrieks up on the other side and commences to pace me as his gleaming multicolored helmet abruptly tilts to study the Porsche's undulating gray shape. Instantly, I switch the EV mode off, causing the 4.6-liter, flat-crank, racing-derived V-8 to explode into a frantic roar, fire-hosing its exhaust into the air through twin, sky-facing pipes. I give him a thumbs-up, too, this time a gesture of communion from one carbon-combustor to another. A telepathic text message is exchanged: Guys love fire! We pace along like this for a while -- me roaring, he shrieking, his helmet fixed in a visual lock on the 918 until he nods and snaps his colorful brain bucket forward and the bike spits away, lane-splitting through traffic. Everybody -- and I mean everybody -- seems to love this car.
However, its amore from humans might be exceeded by its embrace by racetracks. Earlier, the Motor Trend team was at Willow Springs Raceway, where our favorite racing driver, Randy Pobst, belted in and set the production-car track record around the facility's hairy and historic Big Willow. And at California Speedway, the car will break Motor Trend's 0-60-mph record and easily eclipse our long list of figure-eight times.
How does a car accomplish the politically impossible -- get peppered with grins from green-car sophisticates and speed-addled cycle jockeys alike? MIT's Gordon S. Brown once said engineering is the interface between science and society. If so, Porsche's 918 engineers are at the slip-fault interface of the science of mind-bending speed and what's arguably modern society's greatest challenge. The 918 greets both with a solid handshake.
But of course, you say. An $850,000 price tag damn well better afford Zuffenhausen's engineers a big technological toy box to play with. Sure. But if you've been around the razzmatazz/a-sucker-born-every-minute world of supercars for a while, you know Porsche doesn't build a car like this every day.
Super-Porsches appear only periodically, and only when Zuffenhausen decides it's time again to explore new engineering frontiers. It's merely a splendid consequence if the result leaves shattered records in its wake. This became bluntly evident during our day at Willow Springs when a 1986 959 joined our 918 (a prearranged meeting, of course—these things don't just happen, and here's a public thanks to its cool and generous owner). As the gleaming red 959 pulled into the pits, it was as if a rolling Rosetta Stone had arrived. Suddenly, the 918's many technological puzzles seemed to all fit together.
Although performance-oriented AWD and adjustable ride height are almost dime-a-dozen commodities today, in 1986, the 959's parade of unheard-of hardware might as well have been labeled "levitation" and "time travel." While its more lauded contemporary, the Ferrari F40, got greater exposure from the auto paparazzi's flashbulbs, the truth is the technology that made the Italian fast was pretty much dead-end stuff. The 959 was a veritable petri dish of ideas, though, some profound, others just cool curiosities -- a great example being its hollow wheel spokes, which shared the tire's pressurized air. (Why? A wheel crack would also be detected by a drop in tire pressure.) As a Motor Trend staffer quipped, the 959 was a napkin blueprint for the brilliant Bugatti Veyron, 20 years on. Think about it.Flip forward three decades. Unlike in the speed-is-everything 1980s, the 918 is a hybrid supercar thoroughly engaged in the modern sports car's complex new role where nutball speed is companioned by parsimonious efficiency. It'll quietly roll through Europe's zero-emissions city centers one day, and take to the track the next. (Porsche is setting up DC fast chargers for it at major road-racing circuits, including Laguna Seca.) This perceptual change is happening fast: Consider for a second that the next Formula 1 World Drivers' Champion car…will be a hybrid.
As with these new Formula 1 cars, the 918 is part fire, part ice. The stage for both is a carbon-fiber monocoque marvel that encases its engine and lithium-ion battery pack at an elevation almost suicidally close to the asphalt. The fire part starts with the engine's beating heart, a 29-pound "flat," or 180-degree, drop-forged crankshaft spinning in a low-pressure-cast, thin-walled, closed-deck, aluminum-alloy block that's based upon the RS Spyder race cars'. Its dry sump is composed of carbon-reinforced polymer, its oil level is measured by a radar sensor, and its four pumps maintain a vacuum in the crankcase to reduce windage losses. The con rods are titanium, while each piston's weight is whittled down via single compression and oil rings.
Let's return for a minute to its beating heart, that flat crankshaft. It's all about better breathing, and big lungs mean big power -- good for racing. But it's lousy news for secondary vibration, and here's an interesting aside about it: The 918's PDK transmission is actually the 911 Turbo's flipped upside down to lower its weight. However, its shift actuators were being inadvertently triggered by the crank's quivering. Solution: Reorient them by 90 degrees, a change likely to find its way into future 911s. More air is lured in by varying the valve timing (the intake's by 50 degrees, the exhaust's by 55) and by slashing valvetrain friction using followers with "diamond-like carbon" rubbing surfaces and hydraulic lash adjusters, a solution patterned after that of the GT3.
All this lovingly seduced oxygen meets its abrupt doom within eight unusually compact combustion chambers, the charge tightly gripped by a very narrow (25-degree) angle between the intake and exhaust valves, then stomped on by a 13.5:1 compression ratio. The result is the highest power density of any normally aspirated road-going engine, 132 hp/liter, totaling 608 hp at 8700 rpm. Power like that means mucho waste heat, too, so the head's flow pattern has been reversed into what's called Hot Side Inside routing. A compact fabrication of Inconel exhaust plumbing nested in the engine's vee sends the exhaust straight out the top of the engine bay, keeping heat away from the temperature-sensitive battery, as well as creating a cool nighttime light show when blue flames occasionally spasm from the pipes during shifts.
The ice side of the coin is the car's electrification. Slotted between the engine and PDK transaxle is a 156-hp motor that can propel the car, supplement the engine's power, and act as a generator while braking (regen) or even while accelerating (when the engine is instructed to work even harder to restore the battery's state of charge). Up to 93 mph, it's the engine's starter, too, when the clutch between the engine and motor engages as the seven-speed transmission's dual clutches momentarily decouple. A second, 129-hp motor twirls the front axle, decoupling above 165 mph to avoid overspeeding. Having independent electric motors on both axles (along with +/- 3 degrees of active in-phase/opposite-phase speed-dependent rear-wheel steering) affords the car lightning-fast adjustment to its cornering attitude, far quicker than what's achievable via mechanical (driveshaft) redistribution.
Wedged behind the seats is the A/C-refrigerant-cooled battery pack, composed of 312 lithium-ion cells, providing 6.8 kW-hr of energy, of which 5.4 is generally available. In terms of energy, this isn't a terribly large battery as pluggable cars go -- the Honda Accord Plug-in's is 7 kW-hr. But its charge and discharge rates are a certifiably juicy 230 kW. Oddly, its charging receptacle eschews the SAE's new combo plug, the 918's dual AC and higher-power DC charging roles employing a tidier Euro-market plug instead. At its puny 3.3-kW rate, 240-volt AC charging takes about 3 hours; 20 kW DC charging cuts it to about 30 minutes, either one producing 12 miles of EV range. During those miles, the engine can't burn the gas tank's fumes, so the hyperformed aluminum container is insulated with a half-inch of polyurethane foam and pressurized to contain the vapors until the engine restarts.
On his first hard lap around Big Willow, Randy exits the notorious Turn 9 and sirens past. The car's really moving, its combined 887 hp winding it to 162 mph past the pits, but the engine's sound is surprisingly muted, almost like a muffled turbo. Apparently only the birds passing overhead get to enjoy the Porsche's full orchestra of mechanical music from its skyward trumpeted exhausts. A few minutes later, Randy pulls in, and politely asks our Porsche observers for privacy. There's an odd look in his eyes -- "We need to talk."
"The car is just unpredictable," he begins. "On the back straight, there's loads of power; but entering the front straight, it feels like I'm dragging a parachute." (The battery is already getting depleted.) He winces. "And while it turns in beautifully and freely walks its tail around -- things I like -- I can sense lots of computer stuff going on."
More worrisome are the brakes. "The pedal is very firm, but the same effort can get you different results. One time, going into Turn 1 (from 166 mph), it seemed to stop much better for some reason, so I eased off for an instant, and when I got back on the brakes, they were too weak. Nearly went off the road. And, boy, there just isn't the grip I'd expect here from Michelin Pilot Sport Cup 2 tires -- perhaps these have been heat-cycled too many times?" Even though we learn that his best lap, a 1:25.74, is actually the new production-car lap record, it's clear we're sitting at the base of an ominous learning curve. A conference is convened with the Porsche crew. Motor Trend intern Julian Hartig and Porsche technical systems engineer Ken Gould hightail it for Ontario to fetch a new set of wheels and tires while Randy and Porsche's rep noodle out a better lapping strategy.
The new plan is to precede fast laps with slow regen ones to fully replenish the battery while holding the car in Race Hybrid Mode through the early corners (where the engine's extra power is pressed into service generating electricity). Only when he reaches the two high-speed straights will Randy press the go-for-it Hot Lap button, which blows through the battery's energy without attempting to recharge. With the new rubber fitted, the car accelerates away.
Lap one -- bam! -- is a 1:23.54, knocking 2.2 seconds off the record. Randy pulls in. It's still a complicated car to lap, but everybody's smiling now. "I'm getting the hang of it," he begins. "You have to get the lap time done while the batteries are up. And you don't attack the brakes -- you squeeze into them. The hybrid system just requires a new kind of driver involvement and awareness." He continues: "In the 120-mph Turn 8, it's stable and impressively balanced; actually, I'd say its performance is really far more accessible than its older brother the Carrera GT."
Later, at our regular test venue at California Speedway, the car's AWD grip and zero-rpm electric torque rail-gunned it to 60 mph in an insane 2.4 seconds (a record). It also halted from 60 in a teensy 94 feet, pulled 1.12 g while cornering, and blitzed to another record around our figure-eight course, where both Carlos Lago and I sensed what Randy meant about the brakes' unpredictability.
Driving back from Willow Springs in the dark, the 918's various displays glow like the interior of an alien spaceship. The seat, with non-adjustable rake, is upright (as I like it), though the telescoping steering wheel's lack of tilt leaves it a bit high for my taste. Below my forearm is a slick center stack arc filled with touch-sensitive switches and multitouch graphics. (The design is predicted to appear elsewhere in more mundane Porsches. I like it except that the severe angle of its forward controls makes them difficult to read.) Miles pass; the ride quality is surprisingly supple for its track duties and uniball suspension joints. When the battery periodically wears down, the engine abruptly explodes back into frenetic life, annihilating the tranquil tire noise and aero-hiss and making me flinch every time, though the ruckus soon subdues into a curious motorboat burble. Once again in EV mode, the scuffing noise from the brakes is the loudest thing I hear as I touch the pedal to pull off and refill at a Chevron station.
In 2006, we had the chance to test the original Bugatti Veyron, and I think everyone who drove it was awed by its endless acceleration and also left with the bittersweet conclusion that this was the apogee of the supercar. Nothing again would be so shockingly fast or able to stir our imaginations into such a froth.
As I turn into the station, a young guy in a Honda S2000 is pulling out at the same time. He jams on his brakes as his eyes grow wide and his jaw drops. After a few awkward seconds, I wave to him, "Ah, could you move a little so I can pull in?" The jaw remains dropped, the car still frozen. "Dude, can you move your car, please?" Nothing. Amused, I press the button to raise the car's nose, and finally maneuver up the drive around him.
OK, now stop for a second and look at the acceleration graph of the 918 (below) and McLaren P1 alongside the curve we recorded when the Bugatti was introduced. Both the McLaren and the Porsche can now tromp that Bugatti. Think about our Willow Springs record -- and that kid's stunned expression, too. I was wrong about that Veyron. It wasn't the apogee by a long shot.
Three Decades of Porsche Super-NessPorsche's last moonshot road car (discounting the Carrera GT) altered our perceptions of the sports car. It ultimately altered our cars, too. How does the 918 stack up?
|1986 Porsche 959||2015 Porsche 918||% change|
|PRICE|| $225,000 (1986) |
$485,000 (2014 dollars)
|ENGINE||2.9L twin-turbo flat-6||4.6L V-8 + 2 elect motors|
|POWER||450 hp||887 hp (combined)||97% more power|
|TORQUE||370 lb-ft||398 lb-ft (gas) + 430 (elect)||124% more (sort of)|
|TRANSMISSION||6-speed manual||7-speed twin-clutch auto||17% more gears|
|FRONT TIRES||235/45R17||265/35R20||13% wider|
|REAR TIRES||255/40R17||325/30R21||27% wider|
|FRONT BRAKES||12.7 in, steel||16.1 in, carbon ceramic||27% bigger (and carbon)|
|REAR BRAKES||12.0 in, steel||15.4 in, carbon ceramic||28% bigger (and carbon)|
|WEIGHT||3505 lb||3791 lb||8% heavier|
|EV MODE?||No||Yes||infinitely better|
|0-60 MPH||3.9 sec (est)||2.4 sec||38% quicker|
|0-100 MPH||8.3 sec (est)||5.1 sec||39% quicker|
|TOP SPEED||197 mph (est)||214 mph||9% faster|
Red-Hot Tech959: An air-cooled block and water-cooled heads from the 956 race car; twin split-response turbos; 7800-rpm redline; AWD via adjustable clutch; run-flat Dunlop Denloc tires; hollow-spoke wheels; Kevlar body; steel chassis and Nomex floor; adjustable ride height.
918: A flat-crank V-8 derived from RS Spyder Le Mans Prototype racer; 7-hole fuel injectors; adjustable cam phasing; 9150-rpm engine redline; 6 radiators: 3 engine coolants, 1 engine oil, 1 motor, 1 battery; 6.8-kW-hr battery enclosure made of carbon fiber ; carbon-fiber chassis and body; chassis takes 3.5 hours to make; AWD via electric motor on front axle; in-phase/opposite-phase rear-steering; 3-position rear wing and front active diffuser; 657 lb of downforce at 186 mph; front axle lift for road obstructions; braking up to 0.5 g via regeneration alone; EV operation up to 93 mph.
No Respect Look to the LeftRemember when we all thought no acceleration curve would ever be steeper than the Bugatti Veyron 16.4’s? The McLaren P1 and the Porsche 918 almost run away from our original Veyron’s test numbers, though its latest versions might match them. To 60 mph, the AWD Porsche is quickest (2.4 sec); beyond that, the mighty P1 (2.6 sec) edges away. The Bugatti? A yawning 2.7 seconds.
Fratricide at Big WillowThe 911 50th Anniversary Edition, in case you don't know, is a run of 1963 cars celebrating the icon's half-century of continuous production. Based on the Carrera 2, it's fatter Carrera 4 bodywork gives it a more aggressive stance, backed up with 30 extra hp (430), a retuned suspension, plus cool Fuchs-style classic wheels, and tartan 'Pepita seat inserts.
So of course we immediately offered it as a road-course appetizer to the mighty 918. We're not seriously comparing these two, naturally, but rather shamelessly employing the 911 as a baseline to dramatize how insanely fast this 918 is. You can see for yourself their differences in peak speeds between the corners, but let me point out a few, more subtle insights: Generally, their braking rates are quite similar, with the 911 stopping even harder into Turn 3. You wouldn't expect that, but it reflects Randy's enormous confidence in the 911's binders. There's also a slight hitch in the 918's speed in Turn 6; it accelerates so fast out of 5 he has to momentarily breathe the throttle. You don't see this at all with the 911. But forget the details. Just lean back and ponder those two curves: That's what a performance monster looks like.
|2015 Porsche 918 Spyder|
|DRIVETRAIN LAYOUT||Mid-engine, AWD|
|ENGINE TYPE||90-deg V-8, aluminum block/heads, plus 2 perm magnet AC motors|
|VALVETRAIN||DOHC, 4 valves/cyl|
|DISPLACEMENT||280.3 cu in/4593 cc|
|POWER (SAE NET)||608 hp @ 8700 rpm (gas)/ 285 hp (elec)/887 hp (comb)|
|TORQUE (SAE NET)||398 lb-ft @ 6700 rpm/431 lb-ft (elect)|
|WEIGHT TO POWER||6.2 lb/hp|
|TRANSMISSION||7-speed twin-cl auto|
|SUSPENSION, FRONT; REAR||Control arms, coil springs, anti-roll bar; multilink, coil springs, anti-roll bar|
|BRAKES, F;R||16.1-in vented & drilled carbon ceramic disc; 15.4-in vented & drilled carbon ceramic disc, ABS|
|WHEELS, F;R||9.5 x 20-in; 12.5 x 21-in forged aluminum|
|TIRES, F;R|| 265/35ZR20 95Y; 325/30R21 104Y|
Michelin Pilot Sport Cup 2
|TRACK, F/R||65.5/63.5 in|
|LENGTH x WIDTH x HEIGHT||182.9 x 76.4 x 45.9 in|
|TURNING CIRCLE||41.7 ft|
|CURB WEIGHT||3791 lb|
|WEIGHT DIST, F/R||43/57%|
|SHOULDER ROOM||49.5 in|
|CARGO VOLUME||3.7 cu ft|
|ACCELERATION TO MPH|
|PASSING, 45-65 MPH||0.9|
|QUARTER MILE||10.0 sec @ 145.2 mph|
|BRAKING, 60-0 MPH||94 ft|
|LATERAL ACCELERATION||1.12 g (avg)|
|MT FIGURE EIGHT||22.2 sec @ 1.06 g (avg)|
|2.4-MI ROAD COURSE LAP||83.54 sec|
|TOP-GEAR REVS @ 60 MPH||2000 rpm|
|PRICE AS TESTED||$956,675|
|AIRBAGS||Dual front, front side, front head|
|BASIC WARRANTY||4 yrs/50,000 mi|
|POWERTRAIN WARRANTY||4 yrs/50,000 mi|
|ROADSIDE ASSISTANCE||4 yrs/50,000 mi|
|FUEL CAPACITY||18.5 gal|
|EPA COMB/EV EQUIV ECON||22 mpg (gas)/67 mpg-e|
|ENERGY CONS, COMB/EQUIV||153/50 kW-hr/100 mi|
|CO2 EMISSIONS, GAS/EV||0.88/0 lb/mi|
|RECOMMENDED FUEL||Unleaded premium|