Last year’s Boss 302 set new standards for big-pony agility with ‘just’ 440bhp, whereas the new, supercharged 653bhp Shelby GT500 (113bhp mightier than the last) is 100kg heavier, and more savage of disposition.
Much as you'd expect of a 650bhp muscle car with a live rear axle, although that’s not to say the Ford Mustang doesn’t handle. Corners at Brands Hatch were tackled with impressive grip, guided by precise, weighty electric steering. The chassis’s responses were engaging, if not immediate. Throttle take-up was edgy, though, impeding smooth acceleration on exit.
But the GT500’s element is still between the curves, where the most powerful production V8 North America has ever built yields tearaway drag-strip antics of the highest order, soundtracked by deep growls and supercharger whine.
The new, larger Eaton blower generates 56 per cent more boost than the last, while thorough changes to the enlarged yet seemingly unstressed engine include revised camshaft profiles (mimicking the Ford GT) and cross-drilling of the aluminium block and heads.
Our car’s optional Track Pack added yet more cooling for the engine, transmission and differential, the latter being a limited-slip Torsen unit, paired with adaptive Bilstein dampers in the Performance Pack. A carbonfibre driveshaft and upgraded transmission improve refinement.
Adjustable launch control and built-in timing gear complement that purpose, as does the short-throw cue-ball gearknob, which feels like using a pin to marshal an elephant. Standard-fit Brembo brakes admirably and repeatedly shed the momentum.
If you want one, then yes, go for it. Retail price stateside is $54,995 (around £34,300), while unofficial importer Atlantic Sports Cars asks £60,000 here.
Against the less-powerful Corvette ZR1's £106,605, that doesn’t seem so steep.
Ford Mustang Shelby GT500
Price £60,000; Engine V8, 5812cc, supercharged, petrol; Power 653bhp at 6500rpm; Torque 631lb ft at 4000rpm; 0-62mph NA; Top speed 200mph+ (est); Gearbox 7-spd dual clutch automatic; Kerb weight 1620kg; Economy 28.8mpg (estimated); CO2 NA