The high-performance Biturbo diesel variant of the new Vauxhall Astra has been spotted testing for the first time ahead of its planned introduction early in 2016.
The Astra Biturbo, which was announced alongside the new-generation hatchback in September, features a more powerful version of Vauxhall's 1.6-litre 'whisper' diesel engine, producing 158bhp. That engine is already available in the new Astra in both 109bhp and 135bhp outputs.
While some reports have suggested that this test mule is actually the planned Astra GSi, which will get around 247bhp from its 2.0-litre four-cylinder petrol engine, Autocar understands that the model isn't due to arrive until at least 2017. This mule also is also characterised by its twin exhaust pipes - which are known to form part of the Birturbo package.
Minor styling changes inside and out are set to mark the Biturbo Astra out from its regular sibling and will also extend to the Astra Sports Tourer, which also appears to form part of the testing convoy pictured.
Prices for the Astra Biturbo start at £21,395, while the regular Astra range starts at £15,295.