General Motors’ European duo, Opel and Vauxhall, have created a convincingly fresh design and engineering challenge to Volkswagen’s ubiquitous Golf and Ford’s Focus.
It’s no mean feat. Although recent Astra models have been steadily gaining commercial and critical credibility, they generally haven’t managed to attain the overall respect achieved by their archrivals.
But an all-new lightweight vehicle architecture and enhanced chassis and engine capability complemented by impressive added technologies and an interior that provides a surprisingly up-market ambience combine to give the new car added status.
Vauxhall’s UK Ellesmere Port manufacturing facility is the lead plant for the new model (the other is Opel’s Gliwice, Poland factory; design and engineering of the car is centered at Opel Germany) producing both Opel and Vauxhall badged cars in hatchback and wagon (Sports Tourer) configurations.
Depending on the version and its trim level, the latest generation Astra is up to 200 kg (440 lb) lighter than its predecessor. Body-in-white weight is down by about 20% to 280 kg (617 lb).
The new chassis is also lighter by 50 kg (110 lb) despite the fact that it uses no aluminum. Instead, Opel-Vauxhall incorporates high-strength (HS) and ultra-high-strength (HSS) low-weight steels and compact subframes as cost-effective solutions.
This has brought other pluses, said Horst Bormann, Opel-Vauxhall’s Director of Vehicle Performance: “For example, if we reduce bodyshell and suspension weight we can have smaller brakes and that reduces weight further. We can also have smaller wheels and smaller tires—again weight saving.”
To compensate for the aesthetic effects of wheel and tire changes, Design Director Mark Adams gave the Astra a lower, sleeker look, with a falling roof line to the distinctive C-pillar, which helps to enhance the car's individuality, providing “ down road graphics” that can visually separate it from other vehicles in its class. Said Adams: “Basically we have done everything from scratch; the old car was too heavy and we needed to address that, so we fixed the whole package. This is a ‘no excuses’ car now.”
Styling was inspired by Opel-Vauxhall’s 2013 Monza concept.
Adams and his team, working closely with aerodynamicists, have managed to give the Astra a good if not exceptional Cd figure for its class of 0.285. Tweaks that have helped towards this include the placing of exterior mirrors on stalks, with benefits also coming from the C-pillar shaping.
Stefan Fesser, Plant Director at Ellesmere Port, where £140 million has been invested over the past 18 months, said the manufacturing process now includes laser brazing: “Opel has not used this before; we can work with HSS and no longer require spot welding of the roof, saving roof rails and bringing a huge weight reduction.”
The Astra hatchback is slightly smaller externally than the outgoing model, by 5 cm (2.0 in) overall and 2.5 cm (1.0 in) in height, but despite a wheelbase shorter by 2 cm (0.8 in), interior space has increased thanks to the car's new architecture. Unlike the previous platform/architecture, which had to be shared with other distinctly different models such as the Zafira, the new car is using a dedicated solution just for the Astra range. The wagon (Sports Tourer) is expected to be joined by further variants.
At launch, the powertrain line-up for the new Astra range includes diesel units ranging from 74 to 148 kW (99 to 198 hp). Particularly interesting is the diesel 1.6-L CDTi 81-kW (109-hp) ecoFLEX, with stated 82-g/km CO2 emissions and combined fuel consumption of a remarkable 3.1 L/100 km.
A three-cylinder 1.0-L turbocharged gasoline engine is also offered, with 77 kW (103 hp) and maximum torque of 170 N·m (125 lb·ft) delivered at a very low (for a gasoline unit) 1800 rpm. CO2 emissions are stated at a best—for the ecoFLEX version with an Easytronic transmission, stop-start, and low rolling resistance tires—of 96 g/km (99 g/km with the standard five-speed manual), with combined fuel consumption of 4.2 L/100 km. The best zero to 97 km/h (60 mph) time is 10.5 s.
The company is slated to introduce 17 new engines by 2018.
Although Opel-Vauxhall does not pretend that the Astra is entering premium-market territory, its interior does have a perception of "premiumness" about it, particularly in the high-specification versions. Adams' description of it blending “sculptural dynamic shapes, premium materials, and an absolute focus on quality of execution and craftsmanship” may be a shade too lyrical, but it does indicate the essence of the cabin.
Another interesting aspect of the car’s rather cheeky up-market technology message is the option of IntelliLux LED matrix headlights, a system until now firmly associated with the premium sector via Audi and supplier Hella. Opel-Vauxhall's supplier is the Austrian company ZKW. Each headlight comprises eight LED segments, the system automatically and constantly adapting the length and distribution of the main beam. IntelliLux works in concert with a front-mounted camera that identifies oncoming vehicles and switches off relevant LED segments to prevent dazzle.
As the vehicle exits an urban area, high beam lighting is automatically selected and remains on. Studies by the Technical University of Darmstadt, Germany, and the European LightSightSafety Initiative have confirmed the potential for increased safety offered by the system. This editor sampled its impressive efficacy during a night drive in the UK.
The Astra’s technology repertoire also includes torque vectoring and electronic drag torque control to avoid wheel slip caused by high engine drag torque, helping to maintain vehicle steerability.
Suspension is fairly conventional with MacPherson struts front (decoupled to separate the paths of spring and damper settings) and a Watt’s linkage at the rear. Opel-Vauxhall claims to be the first in the world to combine a torsion beam axle with the Watt’s link—and patented it to prove the point. It has been further developed for the new Astra.
Chassis specialist Bormann regards it as providing the dynamic advantages of an independent multi-link setup without the penalties, such as added mass, complexity, and packaging. He added: “We have a new rigidly mounted suspension subframe, which is important. The old car had a much heavier subframe mounted with four bushings. We did a lot of structure test analysis and transfer path analysis and found the rigid mounting to be much more efficient with regard to mass, stiffness, and bending characteristics.”
Torsional rigidity of the body structure is 19,600 N·m (14,400 lb·ft) per degree, a 400 N·m (295 lb·ft) per degree improvement over that of the previous Astra.
Front/rear weight distribution of the hatchback is 60/40 with the battery in the trunk.
The new car is the first Astra to feature OnStar, described by the company as “the ground-breaking connectivity technology now available across Europe.” OnStar includes high-speed 4G LTE mobile network, emergency response notification, and stolen vehicle recovery alert.
Astra is described by Opel-Vauxhall as being one of the first vehicles from a mainstream manufacturer to get Apple CarPlay and Google Android Auto, available through a new version of the IntelliLink infotainment system.
It all adds up to a potentially big step forward for GM Europe.
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