2017 Audi SQ7 TDI Diesel

Not long ago, platform sharing was practically synonymous with old-fashioned badge engineering, that dark period when the only engineering effort automakers put into distinguishing their identikit models went to the formulation of the adhesive required to hold on their brand insignia. These days, platforms are all about shades of gray. Automakers encourage us to think in terms of the sort of scalable architecture that allows cars of radically different shapes and sizes to be spun from the same basic component set. Which is why, even though the Audi Q7 is closely related to the Bentley Bentayga in many ways, it remains very different in others.

V-8 TDI

Yet the new Audi SQ7 has been allowed to cherry-pick many of the Bentayga’s cleverest components, including its active anti-roll system, combining them with a triple-boosted V-8 diesel engine that manages to match the monstrous peak torque of the Bentley’s gasoline-powered W-12. In Europe, where the SQ7 is just going on sale, it’s a little more than half the price of the Bentayga—what’s not to love?

Power comes from what might well be the most advanced compression-ignition engine ever fitted to a road-legal car. This 4.0-liter V-8 has two turbochargers that operate sequentially, the second adding boost above 2200 rpm. The turbines are fed by a novel split-exhaust system that uses Audi’s AVS valve-lift system, a first for a diesel engine. Each variable-geometry turbo is fed by one of the exhaust valves of each cylinder; to bring the second onstream, a sleeve moves on the camshaft to activate that valve.

Clever, but not clever enough for Audi, as the SQ7 also marks the first appearance of the company’s 48-volt electrically powered supercharger. This utilizes a nine-horsepower motor that sits downstream of the intercooler—as close to the engine as possible—to spin its compressor wheel up to 70,000 rpm in less than a quarter of a second, filling in the lag-inducing gap as the turbochargers gather momentum at low revs. As a result, the practically Nepalese torque peak of 664 lb-ft is available from just 1000 rpm through 3250 rpm. That figure also corresponds to the rated limit of the standard eight-speed automatic transmission (which is why it’s identical to the Bentayga’s), and we’re told that, unfettered, the diesel V-8 could generate much more. Audi has built a torquier Q7 before; the first-generation, Europe-only Q7 V-12 TDI had a tugboat-rivaling 738 lb-ft delivered at higher engine speeds.

The SQ7’s visual changes compared with the standard Q7 are relatively minor and follow the playbook Audi uses to create its S derivatives. Most of the metal-look exterior trim is now finished in aluminum effect rather than chrome, and there are silver caps for the door mirrors, fractionally bigger lower air intakes at the front, and special wheels: 20-inchers are standard, but our test car rode on optional 21s, and for those who simply must, there are also 22s.

Sound Off

The first thing you notice about the SQ7’s engine isn’t the torque. That comes later. No, initial impressions on startup are that it sounds pretty much like an old-fashioned, big-cube gasoline V-8. Although the sound is electronically enhanced, opening a window confirms that the soundtrack is similarly muscular outside, and the imitation holds true at higher engine speeds. The SQ7 never delivers any of the tinkling harmonics or induction rush you might expect to hear from such a heavily boosted diesel.­­­

Nor does it perform like one. The V-8’s huge-everywhere torque is indeed impressive, and even at the lowest engine rpm, there’s no discernible hesitation to accelerator inputs beyond the fractional pause introduced by the torque converter. The more abiding takeaway from our first drive is the engine’s enthusiasm to rev. Left to its own devices with the transmission in drive, the engine will shift up at around 4500 rpm, which equates to subjective acceleration forces that feel every bit as substantial as those suggested by our estimated 4.7-second zero-to-60-mph time. But tipping the transmission into Sport mode or taking control of gearchanges manually proves the SQ7 will pull happily, without any top-end hesitation, all the way to its 5100-rpm cutoff. Yes, the W-12–powered Bentayga is faster overall, but the Audi gives away little—if anything—in real-world pace.

The rest of the experience builds on that of the standard Q7. A height-adjustable air suspension and switchable dampers are standard, with European buyers also able to add a sport differential that can vector torque across the rear axle, a rear-wheel-steering system, and—nabbed directly from the Bentayga—an electromechanical anti-roll system. This works to counteract body roll with 48-volt electric motors effectively tightening the front and rear anti-roll bars to counteract cornering forces. (We explained it on the Bentley here.)

Our test car was fitted with all three systems, with the adaptive anti-roll setup working as billed and keeping the big Audi almost flat even under high chassis loads. The overall result is an impressively rapid and agile SUV, but the SQ7 is no sports car. It feels tall and heavy in slower turns, where even the battery of dynamic systems can’t stop the eventual onset of understeer. Grip levels are huge, but handling finesse is slightly less so. The ride is also markedly firmer than that of the standard Q7, even with the Drive Select controller in its most compliant Comfort setting, although the SQ7 felt impressively stable during a brief run at high speed.

In a world where buyers want fast, luxurious SUVs, the SQ7 is pretty much exactly what customers are demanding. The fact that it happens to run on diesel should be an incidental detail; it’s quicker and better-mannered than almost all of the gasoline-powered alternatives. Of course, in the U.S., VW’s emissions scandal has made the SQ7’s diesel engine an issue. Although it has been designed to meet all existing U.S. emissions standards, we’re told that no decision on whether to bring it stateside has yet been made. Audi of America remains optimistic that the case will be successfully made. Here’s to that.

Specifications >

VEHICLE TYPE: front-engine, 4-wheel-drive, 7-passenger, 4-door hatchback

ESTIMATED BASE PRICE: $90,000

ENGINE TYPE: sequentially turbocharged, supercharged, and intercooled DOHC 32-valve diesel V-8, iron block and aluminum heads, direct fuel injection

Displacement: 241 cu in, 3956 cc
Power: 435 hp @ 5000 rpm
Torque: 664 lb-ft @ 1000 rpm

TRANSMISSION: 8-speed automatic with manual shifting mode

DIMENSIONS:
Wheelbase: 117.9 in
Length: 199.6 in
Width: 77.5 in Height: 68.5 in
Passenger volume: 136 cu ft
Cargo volume: 15 cu ft
Curb weight (C/D est): 5250 lb

PERFORMANCE (C/D EST):
Zero to 60 mph: 4.7 sec
Zero to 100 mph: 13.7 sec
Standing ¼-mile: 13.6 sec
Top speed: 155 mph

FUEL ECONOMY (C/D EST):
EPA city/highway: 21/30 mpg