Vauxhall claims that the GTC isn’t just a three-door version of the Astra hatchback and would rather see it positioned – like the Scirocco – as a separate coupé model, distinct from the rest of the range.
“The GTC shares no body panels with either the Astra hatch or Sports Tourer,” Vauxhall claims. And not unjustifiably, it points out that the rakish styling has reached production in a guise that’s faithful to the GTC Paris concept from 2010.
Overall, the GTC’s sleek shape is even longer than the five-door hatch’s at 4466mm (up from 4419mm) and, given the stance, it’s no surprise that it’s also wider (1840mm instead of 1814mm) and lower (1482mm rather than 1512mm). What’s more surprising is that the manufacturer has troubled itself to extend the hatch’s wheelbase for the GTC, by 10mm to 2695mm. The tracks are also wider at the front (up 40mm to 1584mm) and rear (up 30mm to 1585mm).
In part, the suspension’s increased dimensions are because, at the front, it wears a different set-up from the five-door hatch. Instead of conventional MacPherson struts, the GTC was the first Astra to get General Motors’ HiPerStrut system.
In principle, it’s much like a MacPherson strut but with an extra knuckle to bring the steering axis closer to the centre of the driven wheels, reducing torque steer. Ford and Renault have similar systems. The GTC’s steering is electrically assisted and gets a UK-specific tune.
At the rear, the GTC retains the torsion beam and Watt’s link from the five-door Astra, but with extra roll stiffness. Our test car was also fitted with optional FlexRide adaptive dampers. The GTC’s engine range comprises 1.4 and 1.6 turbocharged petrol engines, and 1.7 and 2.0 turbodiesels.