2018 Audi TT RS vs. 2017 Porsche 718 Cayman S
Which German coupe is the more focused driver's car? We find out
Hating turbocharged engines is en vogue among purists these days. When Saab in 1979 introduced the 900 Turbo (it destroyed turbochargers faster than front tires), and when BMW launched the 2002 Turbo (it featured what felt like 10-second throttle lag), the world could not have cared less about artificial aspiration. More than 40 years later, though, at the height of the turbo era and on the eve of affordable electro-mobility, hardcore car guys are mourning the apparent demise of pure and simple old-school drivetrains.
I consider myself part of this group, and I reluctantly admit I wanted to hate Porsche's new forced-induction four-cylinder boxer engine ahead of this test of its new 718 Cayman S and Audi's new TT RS. This engine has, in both Boxster and Cayman, replaced the normally aspirated flat-six. I've been critical of the current breed of let-me-do-this-for-you Audis, thanks to their lack of thrill and enthusiasm. "Androgynous," "aseptic," and "artificial" are terms that come to my mind when sampling these near-perfect but cold products from Ingolstadt. But is this a case of personal preconceptions? Join us for a day of surprises, confirmations, and new findings.
"Anticlimax" is the first thought when you twist the Porsche's lozenge-shaped ignition key and start the engine the old-fashioned way. What disappoints is the noise generated behind your back, a metallic jam-session oddly reminiscent of an Oettinger-tuned Beetle from way back when: plenty of initial clatter and splutter, followed by a hoarse, uneven, and atonal idle. We hoped for a more extrovert performance, even though the tune does get catchier as you select a gear and add revs. There are 7,500 revolutions to play with, plus that optional extra-loud exhaust system acting as mobile speaker array, and yet your ears feast primarily on a dense mix of high-decibel buzz and jarring, bassy rasp.
Let's move over to the Audi, which adopts the racy steering wheel with the big starter button from the R8. Hit that red circle, and people who live on the same street will hate you forever. If the explosive hard-rock intro is anything to go by, this synthesizer has all the marks of the world's first external combustion engine. The initial firings could jerk a baby out of its stroller and make grandpa turn down his hearing aid. Like the 718 Cayman S, the TT RS is fitted with the optional hooligan exhaust, which must have been certified by the Albanian branch of Deaf & Dumb Inc. When pushed through its paces, however, the unexpectedly melodic 2.5-liter alloy-block five-cylinder induces goose pimples and smiles so fast that you instinctively clench your first—well done, Herr composer!
Even before we take off, at mile marker 0.0, the Porsche has some catching up to do. To match the Audi's specification, it is fitted with the seven-speed PDK transmission, not the six-speed manual. In the TT RS, a seven-speed dual-clutch gearbox is the only choice. Next, please erase everything you remember about previous Caymans, because this one is different. High revs required to deliver the goods? Not anymore. At 1,900 rpm, the single-turbo, 2.5-liter engine dishes up 309 lb-ft of torque, and this rich torque menu is available all the way to 4,500 rpm. At the word "go," the new four-cylinder boxer tears down the wall that used to separate cruise mode from instant grunt, which is no mean feat. The secret to this always-on-the-alert attitude is a variable-vane wastegate turbocharger.
Even at part-throttle, it whips up enough boost pressure by synchronizing wastegate aperture, ignition timing, and throttle position. As a result, the 16-valver drops the hammer hard as soon as the driver puts a foot down.
In a very wise move, Audi—under former research-and-development chief Ulrich Hackenberg—developed a new, low-friction, high-efficiency, all-aluminum five-cylinder unit that weighs 57 pounds less than its cast-iron predecessor. Rated at 400 horsepower in the TT RS, the 2.5-liter engine boasts a broader max-torque band than the Porsche engine, spreading its peak twist action of 354 lb-ft from 1,700 to 5,850 rpm. We expected awesome punch in any gear at any time, but there was a snag. When you coast along, for example, at 60 mph and suddenly feel the itch, throttle tip-in is painfully slow; the gearbox takes much too long to change down from fifth to third. Compared to this lengthy pause, normal turbo lag almost feels like a time-warp experience. Audi is aware of this problem and will reprogram the software for hard and fast downshifts.
In the TT RS, seventh is normally a rev-cutting, waft-along gear. In Dynamic mode, however, the black box will zoom in on the bottom six ratios. Although you can slide the shifter across to the manual gate, the steering-wheel paddles are a much more intuitive option. We have also nothing but praise for the PDK box fitted to the 718. Dial in Sport or even Sport+, and the Porsche will change the shift pattern in an even more dramatic fashion than the TT RS. It has to do with how long to hold onto the gear you're in through fast corners and at high or low revs, how to time upshifts and downshifts, and how to best manage the power and torque flow. When fitted with the Sport Chrono pack, the Cayman S features a so-called Sport Response button in the middle of the rotary drive-mode selector. Push it, for instance in preparation of a close overtaking move, and the drivetrain switches to high alert for the next 20 seconds. Also worth noting is the coasting mode, which automatically selects neutral under trailing throttle.
Despite all the marketing efforts, these two coupes are not really brand-new cars. The TT RS's genetic roots trace back to Wolfsburg where Volkswagen developed the MQB architecture now also used by Audi in the 2012 A3 and the current TT. The 718 Cayman is in essence a heavily modified version of the original mid-engined coupe launched in 2006. If you think that's too harsh an assessment, please consider that neither model offers modern conveniences like a head-up display or sophisticated assistance systems. While Audi is rightly proud of its versatile virtual cockpit display, Porsche has at long last introduced a decent infotainment with a new touchscreen and plenty of fresh features. Ergonomically, the latest Cayman S is nonetheless still a hodgepodge of random push, turn, and touch commands. Some of the submenus—case in point is the Individual program—are awkward to access, the main dials including the digital speedometer are too small, and the center stack is cluttered.
The TT RS cabin is a nicer place to be. Where the Porsche has a firewall, the Audi has two token rear seats that fold down to increase the luggage space. It also sports more head- and legroom, easier-to-use controls, and a more stylish cockpit equipped with more modern materials. While the car from Ingolstadt comes with Quattro all-wheel drive, S-tronic transmission, and 19-inch wheels, the guys from Stuttgart make you pay extra for the dual-clutch gearbox and bigger wheels and tires.
As far as costs go, well, Audi has not yet priced the TT RS for the U.S., but we expect it to start at about the same price as the PDK- and Sport Chrono-equipped Cayman S. For the first time in its life, the 2017 Cayman is actually less expensive than the corresponding Boxster. It may not mean much, but the TT RS loses only two-tenths against the R8 V-10—which costs more than twice as much—in the 0-60-mph trial. In the same discipline, the 718 equipped with the PDK, Sport Chrono package, and launch control beats the base 911 Carrera that carries a 50-percent price premium. There is no doubt: The days when the number of cylinders and amount of displacement determined a car's performance are over.
When speed is a drug, then this colorful couple will get you hooked for life after a single day's hard driving. One is almost always going too fast on those empty B- and C-roads in the Regensburg hinterland, and even on the unrestricted Nuremberg-Munich autobahn, the fast lane was rarely clear enough to reach terminal velocity. The Audi normally tops out at 155 mph, but our test car came with an extra-cost 175-mph speed limit.
Even at that velocity, there was still a bit of forward thrust left. Officially, the Cayman S will do 178 mph. We saw an indicated 186 mph moments before another mirror-less and indicator-less holidaymaker pulled out in front. Slamming on the brakes accomplished reassuring deceleration, but the freeze-frame effect was even more mind-boggling in the TT RS fitted with carbon-ceramic reins up front. The Porsche, which relied on steel rotors all round, is also available with compound stoppers. Sadly, they cost about as much as a small farm in Swaziland.
What sets these two cars apart philosophically is one simple fact: The Porsche is a sports car, the Audi is a very sporty car. Compare, for a start, the driving positions. In the 718, you sit low down, close to the road, under a low roof. The TT RS is much easier to get in and out of, the position behind the wheel is more relaxed, the roof peaks at a less extreme height. But the Audi is clearly more A3 than R8, despite the red stitching, the fancy instruments, and that fixed wing in the rearview mirror. What splits the hatchback coupes dynamically is the steering. The Cayman S uses the same rack as the 911 turbo, one of the most satisfying man-machine interfaces. The TT RS benefits from a variation of the MQB steering, which offers three different settings labeled Comfort, Auto, and Dynamic. I give it only 7.5 points on the total immersion scale, where the Cayman scores a solid 10.
Depending on your definition of perfection, the Audi comes close to being one of the easiest cars to drive fast, irrespective of road and surface conditions. Instead of bothering you with too much information, it likes to act as a sublime filter with a twist. The steering is slightly over-damped, over-assisted, and over-eager to step in. Somehow, it seems to have a life of its own, and the mission of that life is to absorb or enhance, depending on the situation. Along with torque vectoring, it will, for example, miraculously pull the car straight again at the exit of a bend or under hard braking into a downhill corner.
But a committed driver might be reluctant to accept any intervention, unless we're talking true life-saving devices like anti-lock brakes or skid control. Once again, this Audi struggles to fuse maximum active-safety features and total involvement. The Porsche allows more leeway and provides more freedom, it still inspires confidence despite the longer leash, and it has been engineered for absolute interaction. The steering plots the tarmac with rare accuracy, even though this setup accepts, to a certain degree, vibrations, kicks, and nudges. Since the communication is totally authentic, you always know exactly what the car does, and what it will likely do next. And here's the thing: Porsche still champions the fixed steering-calibration strategy en lieu of a variable-this-or-that gadgetry. This parameter can make all the difference. The main active-safety device installed in the Audi is Quattro all-wheeel drive. In foul weather and on slippery turf, a hard-charging TT RS remains relatively unperturbed while the Cayman S has long entered phase-two twitchiness. Does this focus on active safety make your heart beat faster? Probably not. Does it make the drive home less challenging? Absolutely.
Click the thumbwheel from Comfort to Sport, and the Porsche flexes its muscles instantly. Twist it one notch further to Sport+, and the car prepares for a racetrack visit. Your best bet is thus perhaps Individual mode, which can, for example, blend compliant dampers with fast shifting and eager throttle response.
Better still, dial in PSM Sport, which is, on cold tires, almost as exciting as PSM Off. If testing boundaries is all about putting abilities and ambitions into perspective, then the 718 is a better tool for this job than the TT RS. It simply is the more tactile car, provides feedback in abundance, talks you through the tricky bits with subtle body language, and leaves some latitude before stepping in. The Cayman is happy to indulge in the complete handling spectrum from mild understeer to wild oversteer. It is a classic case of challenge followed by instant reward—or instant punishment.
Having said that, the Audi is on certain days the quicker A-to-B car. Its trick driveline now boasts wheel-selective torque delivery, the cornering grip of the 20-inch Pirelli P Zeros (the Cayman ran on the same tire type) is little short of phenomenal, and in Dynamic mode more grunt can be relayed to the rear wheels in the blink of an eye.
Through fast sweepers, the TT RS is surreally fast, poised, and grounded. Where ripples and grooves start to annoy the Porsche, its challenger continues to be an unreservedly focused, unswerving carver. Even though the 718 received the 911's four-piston front brakes, it cannot quite match the fast-rewind stopping power of a TT RS with carbon-ceramic rotors. Another forte of the coupe with the four rings is the sprint against the stopwatch. Thanks to Quattro, launch control, and an extra 45 lb-ft of torque, it beats the Porsche by a significant half-second from 0 to 60 mph.
At the end of the day, the TT RS's handling balance costs it precious virtual points. How come? Because turn-in just isn't quite as eager, and because eventual understeer is the name of 10/10ths cornering exercises, and because the car likes to be in control. When we entered the zig-zag roller-coaster part of the route, the TT RS started with a tire pressure of 33 psi all-around. About 40 minutes later, rubber melting and brakes fuming, the readout signaled a jump to 48 up front and 38 in the back. Sure, we could have let air out and hoped for the best on the re-run. Alternatively, though, Audi could have agreed on a more adventurous torque split not unlike the setup Ford chose for the remarkable Focus RS. After all, truly fast cornering is not about overt leeriness but about a predominantly neutral attitude that stretches a bit either way when required.
On paper, these two contenders have a lot in common. On the road, however, they display quite different strengths and weaknesses. The TT RS wears a flashy, aggressive outfit, but it delivers when pushed, and its dynamic potential is remarkably accessible. The 718 Cayman S is a more complete car than last year's GTS, and it ticks all the critical boxes, moving one more step closer to the 911. Despite the paradigm shift toward the turbocharged flat-four engine, it still is the more emotional choice, the more engaging drive, and the sole proper sports car.
2017 Porsche Cayman S Specifications
|Price:||$70,550 (base with PDK transmission)|
|Engine:||2.5-liter turbo DOHC 16-valve flat-four/350 hp @ 6,500 rpm, 309 lb-ft @ 1,900-4,500 rpm|
|Layout:||2-door, 2-passenger, mid-engine, RWD coupe|
|EPA Mileage:||20/26 mpg (city/hwy)|
|L x W x H:||172.4 x 70.9 x 51.0 in|
|0-60 MPH:||4.0 sec|
|Top Speed:||177 mph|
2018 Audi TT RS Specifications
|On Sale:||Spring 2017|
|Price:||$68,000 (base) (est)|
|Engine:||2.5-liter turbo DOHC 20-valve inline-5/400 hp @ 5,850-7,000 rpm, 354 lb-ft @ 1,700-5,850 rpm|
|Layout:||2-door, 4-passenger, front-engine, AWD coupe|
|L x W x H:||165.0 x 72.1 x 52.9 in|
|0-60 MPH:||3.5 sec|
|Top Speed:||155 mph (175 with optional package)|