It's not much of a stretch to say the horsepower wars have gotten a bit ridiculous these days, especially when it comes to big luxury sport sedans. In the early 2000s, cars such as the Audi RS 6, BMW M5, and Cadillac CTS-V made 444, 394, and 400 horsepower, respectively. Nowadays, their descendants churn out 552, 553, and 640 hp. So what are enthusiasts to do if they want a luxury sport sedan without the impending fury of 640 hp a toe away?
Thankfully, a handful of other cars fill the gap—all with badges signifying some of the performance potential of the top-of-the-line models but without the price tags, fuel economy penalties, or inevitable domestic squabble after you've gone through your third set of tires in just as many months. These three "compromises" represent two of our old favorites and one newcomer.
Representing Germany is the 2016 Audi S6. Yeah, we could've invited a BMW 550i with the M Sport package or a Mercedes-Benz E400 with some AMG-branded door pins, but to us, the updated-for-2016 S6 better represents what this niche segment is all about: a balance of luxury, performance, and drivability. The key to the trifecta of Teutonic goodness lies under the S6's hood, where a thunderous twin-turbo, 444-hp V-8 lives, and it's just as happy loping along around town as it is banging off its limiter.
The other old favorite proudly represents the red, white, and blue. The 2016 Cadillac CTS V-Sport follows the tried-and-true luxury sport sedan blueprint: potent engine—in this case a 420-hp, twin-turbo V-6—a featherweight chassis, and drop-dead good looks. The combo was good enough to earn our Car of the Year award just two years ago, and it still remains a must-drive.
As for the newcomer, well, this one might leave you scratching your head, but hear us out: the 2016 Lexus GS F. The GS F at first glance seems destined for comparison tests with the Audi RS 7 or Cadillac CTS-V, yet its V-8 just doesn't hang with the big boys. Bringing the GS F to a CTS-V and RS 7 comparison test would be like bringing a squirt gun to a bazooka fight. Putting it up against the S6 and CTS V-Sport evens the odds for the Lexus and provides a serious challenge for those two rivals.
The winner will offer up the best balance of luxury, performance, and real-world and track drivability.
All three of our contenders follow the same general formula. The most powerful of the bunch, the Lexus GS F, showcases Lexus parent company Toyota's aversion to forced induction with a wonderful naturally aspirated, 5.0-liter V-8 making 467 hp and 389 lb-ft of torque paired with an eight-speed automatic transmission that sends power out through a trick driver-controlled rear differential.
Cadillac made a name for itself selling big, heavy luxo-barges, but the CTS V-Sport displays the brand's newfound penchant for smaller engines, more power, and less weight. The CTS V-Sport's 3.6-liter, twin-turbo V-6 is the smallest and torquiest engine here, making 430 lb-ft of twist. As in the Lexus, power is routed rearward through a traditional eight-speed automatic.
As you'd expect from Audi, the S6 differs from its two rivals in its drivetrain. The S6 sports a 4.0-liter V-8 with two turbos mounted right inside the vee under its hood. The V-8 sits in the middle of its rivals when it comes to power—444 hp and 406 lb-ft of torque—but its seven-speed twin-clutch automatic and all-wheel-drive system set it apart from the Cadillac and the Lexus.
Given that the players in this segment straddle both the luxury and performance realms, they'll be judged as such. The winner won't necessarily be the fastest or pull the most g's, nor will it be the cushiest cruiser, but it will offer up the best balance of luxury, performance, and drivability both at the track and in the real world, where these cars will spend most of their lives.
Our evaluations start in Los Angeles' ritzy but rain-soaked Rancho Palos Verdes. Our drive loop replicates how we imagine the wealthy buyers of these cars will actually use them—heavy on in-town driving with some quick, hilly, twisty roads thrown in to replicate the escape to the owner's mountain retreat. Afterward, we head east in search of a metaphor, toward a powerplant in Palm Springs to rack up some highway miles. We wrap things up at our Fontana test track after some instrumented testing.
From the get-go, the S6 revealed itself to be cut from a different cloth than the other two cars. The why is initially hard to pin down, but it boils down to it being much more mature than the Cadillac or Lexus. Think Johnnie Walker Gold versus Johnnie Walker Black. The maturity factor is apparent from the first glance at the Audi's sheetmetal. "It's technical, sporty-ish, inoffensive, like a North Face pullover," editor-in-chief Ed Loh said. And just like a North Face, the all-wheel-drive S6 proved itself plenty capable during the pouring rain we experience on the first day of our evaluations. The twin-turbo V-8 and seven-speed dual-clutch combo is a force to be reckoned with. Quiet and out-of-the-way in Comfort mode, the powertrain really wakes up in Dynamic mode. The transmission bangs off blitzkrieg-quick shifts, and the V-8 offers up wave after wave of torque to surf. "This motor is under-stressed and simply magnificent," senior features editor Jonny Lieberman said. "The eight-banger is also perfectly paired to Audi's quick-shifting, seven-speed dual-clutch transmission, arguably the best cog-swapper of the bunch."
The Audi's torque-vectoring all-wheel-drive system was also much appreciated in the flooded L.A. streets, though it did have some downsides—chiefly its rather sluggish steering feel. The S6 is sure-footed, but there's no fighting physics—its V-8 is still hanging right off the Audi's bow, forward of the front axle. "The Audi's tiller felt sluggish," Lieberman said. "Comfort mode felt disconnected, and Dynamic is too heavy while still feeling disconnected."
The S6's air suspension, which gives it the plushest ride of the bunch, also doesn't help things much when it comes to corner carving. "The tightness of the chassis compared to the plushness of the suspension only highlights the gluey and artificial feeling of the electric power steering," Loh said. "It's like night and day when compared to the CTS and Lexus—especially at parking lot speeds."
Where the Audi S6 really starts to make sense is in a straight line. "This car is a total cruiser," associate online editor Stefan Ogbac said. "It's at home devouring long stretches of highway at extremely high speeds." Testing director Kim Reynolds agreed, finding it "a very satisfying on-road conveyance." What makes the S6 so great to drive over long distances is not only its plush ride and powerful engine but also its interior. Although the other two are nice inside in their own rights, the Audi package is the most complete with attractive, high-quality leather and the best infotainment system of the trio.
At the test track, the S6 is a solid performer. Its all-wheel-drive-aided 0-60-mph run of 3.8 seconds is the quickest here. The Audi's quarter-mile time of 12.4 seconds at 111.4 mph is also the fastest of the group, although it begins losing steam by the end of the quarter. The Audi's figure-eight performance falls in line with what we observed during our road loops—its 24.9 seconds at 0.77 g average lap is the slowest of the three, and its 0.91 g average of lateral acceleration is the lowest, as well.
Although we all enjoyed our time in the Audi S6, for us it was too singularly focused on straight-line speed and not focused enough on being a jack-of-all-trades sport sedan. There's absolutely something to be said for its long-distance cruising ability, interior amenities, and performance numbers, but our other two competitors provide an better balance than the S6.
With its gaping maw and Nike swoosh daytime running lights, the Lexus GS F sits at the opposite end of the spectrum. Whereas the Audi emphasizes comfort, the GS F focuses on sportiness, so long as you're out of the default Normal drive mode. In Sport and Sport+ modes, the 5.0-liter V-8 sounds burbly and aggressive and the eight-speed automatic responds quickly to changing throttle demands. The Lexus feels most at home in these more aggressive drive modes, the engine happily singing to its high rev limiter as the transmission snaps off shifts. "Great engine," Lieberman said. "Loved it in the RC F; love it much more in the GS F."
The GS F is a touch less thrilling at more sane speeds. Although steering response remains pleasantly sharp in Normal mode, the throttle and transmission tuning is a bit of a letdown. Throttle response in the default drive setting is muted, and the transmission is reluctant to shift down a gear or three when called upon. "When cruising, the transmission in Normal and Eco will not kick down for a good second and a half when floored," Loh said. "The delay feels like eons when you're trying to drive fast." Somewhat at odds with Lexus' origins as a company making comfortable luxury cars, the GS F's ride is on the stiffer side. The Lexus' suspension, unlike the Audi and Cadillac's, is nonadjustable—it's set from the factory for track work. That and the GS' already stiff chassis make for a ride that borders on harsh on California's poor roads. "The dampers transmit a lot of vibration and shock to the driver," Loh said. "I had a noticeable amount of head toss and belly jiggle, and my belly ain't that big."
The head toss and belly jiggle are further compounded out on the highway, where the suspension struggles to mask road imperfections. The ride is properly stiff—an electronically adjustable suspension with a Comfort mode would be near the top of our list of wants. The quick steering ratio also means the Lexus struggles with straight-line stability at highway speeds, requiring near-constant corrections from the driver to stay in the lane.
With the exception of a few hard-to-find buttons (go ahead and find the parking brake, we dare you), the interior is well-executed. The brasslike trim materials are a neat touch, and we're big fans of the red leather seats. "It looks the most like an $85,000 car," Loh said of the interior, "so long as you don't look too closely at the navigation screen." The TomTom-esque Lexus navi screen and mouselike joystick control for the infotainment system do much to ruin an otherwise solid interior. Lieberman: "How on earth did this get past the beta stage?"
Our guess? Lexus was far more focused on outright performance. Zero to 60 mph takes the GS F 4.4 seconds, and its quarter-mile time is 12.8 seconds at 112.2 mph, which is the fastest trap speed of the bunch. With its rear diff in Slalom mode, the GS F posts a 24.3-second figure-eight lap with a 0.81 g average. "Easy to drift like mad," the normally reserved Reynolds said, "so much so that it's easy to get carried away and do too much."
We went back and forth on placing the Lexus in first, but what sunk it in the end was its highway performance and its price. Yeah, the GS F is quicker than the CTS V-Sport, but is it $14,000 quicker? For our money, no. "I dig the GS F," Lieberman said. "Problem is, for the money you'd pay for the GS F, you could have the 640-horsepower CTS-V. Badge snobbery is a thing, but in this case, it's straight-up ridiculous."
The Goldilocks of the trio is the Cadillac CTS V-Sport. It's neither too soft nor too stiff; it's just right. On our road loops, the CTS expertly balances ride quality with handling prowess. The magnetorheological shocks ride well over poor roads and help the V-Sport rip around corners at speed. The nice, meaty steering wheel offers up plenty of road feedback and excellent turn-in. "I can't believe how far Cadillac has come from waterbed cornering and Cool Whip steering," Loh said. "There's nothing soft or light about this beast; everything is thick and requires a bit of manhandling, from the thick-rimmed steering wheel to the, erm, erect shift lever."
Speaking of shifting, we're mighty pleased with the eight-speed auto's updated shift mapping. Shifts are now quicker and smarter than before, taking full advantage of the twin-turbo V-6's massive torque curve. "I really dig driving this car," Lieberman said. "I can't emphasize enough how great this car's steering feel is. Joyful—there's no other word for it."
These three offer top-of-the-line performance potential without the price tags or fuel economy penalties.
Things are pretty good out on the freeway, too. The Caddy is comfortable, buttoned-down, and quiet out on the open road. The CTS V-Sport is planted and confident at speed, the electromagnetic suspension isolating the driver from poor pavement. "Magnetic Ride Control really shines on the highway," associate online editor Erick Ayapana said. "It soaks up bumps without transmitting any harshness to the cabin." The cabin itself is "brutish and hypermasculine," as Loh put it, with gorgeous baseball-glove leather and open-pore wood trim. Although backseat accommodations are tight, the front seats are comfortable with a commanding driver's position. Cadillac's CUE infotainment system remains a bit of a disaster, but hey, at least it's now compatible with Apple CarPlay and Google Android Auto.
Despite the 50-horsepower gap between it and the hot rod Lexus, the Cadillac CTS V-Sport puts up quite a show at the dragstrip. The slick black Cadillac accelerates to 60 mph from a standstill in 4.7 seconds and on through the quarter mile in 13.1 seconds, trapping at 109 mph even. The Cadillac splits the difference between the GS F and S6 on figure-eight time, lapping the course in 24.7 seconds averaging 0.80 g.
The Cadillac might not be the quickest car of the three, but the balance of driving dynamics, comfort,luxury, and value push it over the top. This is a Cadillac that will surprise people who'd otherwise never consider buying one. It's a driver's car, a luxury cruiser, and a killer value. Cadillac may not yet be the "Standard of the World" again, but it's well on its way.
As close a third-place finish as could be, the S6 is a little too soft for our tastes, but it's a stellar car nonetheless.
If this comparison test were purely about performance, the tightly wound GS F would have rightfully won the gold.
Yeah, GM has been winning lots of awards lately, but when you're churning out fantastic world-beating cars such as the CTS V-Sport, praise is warranted.
With our three sporty cars each making more power than their supersedan predecessors, we turned the clock back to see how the originals stacked up.
The CTS-V made its debut with a 5.7-liter V-8 making a modest 400 hp and 395 lb-ft of torque. The 420-hp CTS V-Sport's twin-turbo V-6 matches the original V's 0-60 and quarter-mile times.
"The Caddy's turn-in is scalpel-sharp, the front end bites hard, and just as the car is beginning to push, a squeeze on the throttle brings the rear end out ever so gently and the nose back in line. Few sport sedans—or sports cars, for that matter—are so beautifully balanced and neutral." Arthur St. Antoine, February 2005
The 2003 RS 6 makes its power from a 444-hp, twin-turbo V-8. The bigger engine on the RS 6 makes a hair more torque, but its five-speed auto won't launch as quickly as the seven-speed dual-clutch in the S6.
"Press as hard as you like on the throttle—anytime, anywhere—and the Audi rushes forward in a muffled whoosh of pressurized potency. No hiccups, not so much as a chirp from the tires. The RS 6 spools up with so little drama, it doesn't feel as quick as it is." Arthur St. Antoine, September 2003
In the early 2000s, the GS 430 was the sportiest four-door Lexus sedan you could get. Its lazy but refined 4.3-liter V-8 can't hold a candle to the GS F, but its 300 hp puts it in line with the current Lexus GS 350 F Sport's 311-hp V-6.
"The five-speed transmission kicks down, the tail squats slightly, and you'd better have the vehicle pointed in the right direction. Hit the brake pedal and hope nobody's tailgating you: The GS 430 goes from 60 to parked in an amazing 108 feet, just a handful of feet more than a Corvette Z06." David Newhardt, June 2001