Opel Magazine. The magazine for Opel drivers and friends.

The Astra GTC’s perfect roadholding is the result of a combination of HiPerStrut front suspension and a compound crank/Watt’s link rear axle.

1. The GTC is the first Astra to feature an exclusive high-tech detail: the Insignia OPC’s HiPerStrut front-wheel suspension. This is included in all versions, and has been adapted for the compact sports car to achieve the improved handling and more direct steering response favoured by sports drivers. Opel’s engineers have redesigned the Astra’s MacPherson struts to use the same suspension points.

2. HiPerStrut stands for high-performance strut. The new design reduces the kingpin angle by 44% and decreases kingpin offset at the hub by 46%. This in turn reduces torque steer and camber loss, and improves roadholding. As a result, the Astra GTC has a more neutral stance when cornering, taking bends faster, and more precisely, and giving direct feedback.

3. The improved wheel envelope curve (the amount of space taken up by the wheel during steering and spring deflection) means that larger tyres can be used with wheel diameters of up to 20 inches. This exclusive design makes the coupé “stick” to the road.

4. The Astra GTC’s clever combination of a compound crank and Watt’s link rear axle has already proved its many benefits in the Astra. Two cross-struts to the wheels form a central component of this system.

5. The cross struts are attached to a short, pivoting centre link with a ball joint at each end. During cornering, this arrangement offsets the compressive force on the outer edges of the cross struts against the tensile force on the inner edges.

6. The axle profile maintains camber stiffness against lateral forces. It twists during cornering, minimising body roll and correcting the car’s track.