The combination of a racetrack and an SUV always feels like an unlikely one, even if it can also be hugely amusing. The prototype version of the Aston Martin DBX 707 proves both points as it laps the petite 1.1-mile Stowe circuit at Silverstone that Aston uses for high-performance testing. Before my drive, a stint as a passenger with CEO Tobias Moers driving proves that the 707 is capable of demolishing Stowe's short straights in a wave of V-8 fury, and also that it is capable of generating some impressive angles of power oversteer.
Yet Moers is keener to demonstrate the new range-topping DBX's low-speed ride than he is to shred tires, leaving the test track to take a tour of Silverstone's bumpy access roads to show the firmed-up suspension settings haven't come at the expense of compliance. Suspension changes include new top mounts at the front and stiffened geometry, with slightly softer dampers at the rear to improve traction. "The car cannot be too aggressive," he insists, steering toward potholes to prove his point. "That would ruin it." Nobody could accuse Moers of not being a hands-on leader.
The headline power figure is certainly impressive: The 707 metric horsepower of the car's name translates to 697 horsepower. But changes to the 4.0-liter AMG V-8 are surprisingly slight: new ball-bearing turbochargers and redesigned induction and exhaust systems, plus a revised ECU. Moers confirms the engine's bottom end is unchanged—as the man who commissioned the V-8's creation in his previous role as head of AMG, he knows its capabilities as well as anyone. The most significant powertrain change is the arrival of a new wet-clutch nine-speed transmission, which has planetary gears like a conventional automatic but uses a clutch pack instead of a torque converter to improve off-the-line response. Moers returns to the Stowe circuit to demonstrate that response using the 707's brutally effective new launch-control function.
But this isn't just a passenger ride, despite the enjoyable novelty of being chauffeured by the CEO. After another couple of laps on track Moers returns to the pit lane to relinquish the driver's seat and says, "You will learn more sitting on this side."
I do. Firstly, that the prototype DBX 707 feels just as fast from behind the wheel as it does from the passenger seat. Aston's claimed 3.1-second zero-to-60-mph time sounds ludicrous enough when you consider the 707's stated 4950-pound curb weight, but it is the company's 7.4-second zero-to-100-mph claim that's actually more surreal. That would make it just 0.1 second slower than the Jaguar XJ220 supercar's time—the Jag having been the fastest production car in the world when new.
Acceleration forces almost feel uncomfortable, the DBX 707 launching hard and devouring the relatively short gearing of its nine-speed gearbox so quickly that, when shifting manually, it's challenging to keep up with the engine's ravenous demand for new ratios. The regular DBX is not a slow car, but the 707 feels like it's in an entirely different league, especially given the bellowing soundtrack of the new exhaust.
The standard fitment of carbon-ceramic brakes, the front discs a monstrous 16.5 inches in diameter, seems like a prudent one. At Silverstone, the prototype's pedal nonetheless started to soften after several hot laps—a non-finalized pad compound was said to be the cause—but the finished system should be capable of handling the enormous thermal loads the car will be able to generate.
Although we suspect that few buyers will choose to regularly take their vehicles on track, the DBX 707 acquitted itself well on the dinky circuit. Grip levels from the monstrous optional 23-inch Pirelli P Zero tires are huge, and although it wasn't hard to engender understeer on Stowe's tighter turns—the laws of physics being immutable after all—it never felt excessive. And it was just as easy to throw the 707's handling balance dramatically rearward under power.
Like the regular DBX, the 707 has GT, Sport, and Sport Plus modes, which progressively increase the torque-vectoring effect of the active rear differential to help the car turn and also send more of the engine's output to the rear axle. The stability control also has a more permissive Sport function, which allows significant power oversteer before intervening. The heroic (or foolhardy) can switch it off entirely.
But even well short of hoonery, the revisions can be felt. The tightened front end has removed any sense of slack from the 707's steering, and although no more force is required to turn the wheel than in the standard DBX, there is definitely more feedback. (On reflection, it felt very AMG-like, which, given Moers' past life, is entirely unsurprising.) The fundamental pliancy of the air springs, and what remains generous suspension travel, kept the ride compliant over Stowe's curbing despite the huge wheels. And the 48-volt active anti-roll system helps to minimize lean and keep the 707's mass under tight control during directional changes. We will need to wait until a road drive in the finished car to assess the real-world compliance, but early signs are positive.
Other changes to the 707 include a more muscular body kit, although one that still stops well short of the theatricality of the Lamborghini Urus. It also gets new seats, which gripped well on track, plus a revised center console with a rotary selector for the various dynamic modes and separate buttons for the adjustable dampers, stability control, and the exhaust's acoustic flap. It still doesn't have a touchscreen interface, though—Moers says the creation of a new, bespoke UI system is one of Aston's top priorities.
Beyond broadening the appeal of the DBX range, the 707 has another mission. That is to prove itself the fastest SUV in the world, or certainly the quickest around the famous 12.9-mile Nürburgring Nordschleife. The current SUV record is 7:39, set by the Porsche Cayenne Turbo GT last year, and although Moers refused to nominate a target time, it's clear he expects the 707 to be quicker. We're not entirely convinced, because our own Cayenne Turbo GT straight-line test results don't just best Porsche's claims, they also eclipse Aston Martin's estimates for the DBX 707.
Aston Martin reckons the 707 will make up more than half of the DBX's sales volume, despite a $235,086 starting price that makes it nearly $50,000 dearer than the standard version. Yet, while the standard DBX offers an impressively Aston-like driving experience, it isn't close to the front of its ludicrously fast segment when it comes to raw performance. The 707 is set to redress that situation, and how. Don't be surprised if the production version proves itself the fastest SUV of them all.