Aston Martin DBXS

THE name '707' certainly has a nice ring to it, so it seemed a fitting choice for the range-topping version of the Aston Martin DBX.

- Alex Ingram

When that number is a direct reference to a car's metric horsepower output, it becomes a pretty wild name to have, too.

But now, the 707 has been upstaged by this: the new DBX S. It's a less dramatic-sounding name, sure, but the S actually carries more weight in the marque's history, sitting on a range of more sporting models since the fifties. In this case, it also carries more power and - if you tick the right option boxes - less weight than the former pinnacle of Aston's SUV range, too.

The power side of the equation has been taken care of by engineering know-how gathered during development of the new Valhalla. The Mercedes-AMG-derived 4.0-litre twin-turbo V8 was further updated in Aston Martin's mid-engined supercar, gaining revised turbos with larger compressor-wheel diameters and tweaked internals. That tech has found its way into the DBX S, with the addition of a revised exhaust system complete with vertically stacked tailpipes.

The result is 717bhp. Given that the 707 made 697 mechanical horsepower, that's a 20bhp increase on before, gains which Aston Martin claims add a little more urgency towards the top of the rev range. The DBX S's torque figure is 900Nm, which is the same as the 707's.

A car as large and heavy as a luxury SUV needs all the help it can get to shed a few pounds, and Aston Martin's focus has been to trim the weight in the most useful places. Among the most striking is a carbon-fibre roof. This panel, which also ditches the standard roof rails, shaves 18kg from the car's highest point to lower the overall centre of gravity. Further down, the vast 23-inch wheels can be made of optional lightweight magnesium, removing a further 19kg of unsprung mass (which allows the suspension to better control itself) relative to the standard forged aluminium items.