Vauxhall Signum (facelift ) 2.8 Turbo V6 (250 Hp)

The Vauxhall Signum, particularly the facelifted version introduced in 2005, represents a unique offering from the British automaker. Positioned as a hatchback – though often described as a ‘sports hatch’ – the Signum aimed to blend the practicality of a family car with a more dynamic driving experience. While never officially sold in the United States, the Signum was a significant model for Vauxhall (and its sister brand Opel) in Europe, competing with vehicles like the Ford Mondeo and Volkswagen Passat. The 2005 facelift brought styling revisions and, crucially, the introduction of a potent 2.8-liter Turbo V6 engine, the focus of this article.

Vauxhall Signum (Facelift 2005) 2.8 Turbo V6: An Overview

The Signum, launched in 2003, was based on the Opel/Vauxhall Vectra platform but distinguished itself with a more distinctive fastback profile and a focus on interior space and flexibility. The 2005 facelift refined the exterior styling and, more importantly, introduced a range of updated engines, including the flagship 2.8-liter Turbo V6. This engine provided a substantial performance boost, elevating the Signum’s appeal to drivers seeking a more engaging driving experience. Production of the facelifted Signum continued until 2008, after which the model was discontinued without a direct replacement.

Engine & Performance

The heart of the 2005 facelifted Signum 2.8 Turbo V6 is its Z28NET engine, a 2.8-liter (2792 cm³ or 170.38 cu. in.) V6 powerplant. This engine utilizes a turbocharger and intercooler to produce 250 horsepower (Hp) at 5500 rpm and 350 Newton-meters (258.15 lb.-ft.) of torque available from 1800 to 4500 rpm. This broad torque curve provides strong acceleration across a wide range of engine speeds. The engine’s power output translates to a weight-to-power ratio of 6.6 kg/Hp (151.5 Hp/tonne) and a weight-to-torque ratio of 4.7 kg/Nm (212.1 Nm/tonne), contributing to its responsive performance. The engine features multi-port fuel injection and a Double Overhead Camshaft (DOHC) valvetrain with four valves per cylinder. Power is delivered to the front wheels via a six-speed manual transmission. The Signum 2.8 Turbo V6 is electronically limited to a maximum speed of 250 km/h (155.34 mph).

Design & Features

The Vauxhall Signum is a five-door hatchback, offering seating for four passengers. Its design emphasizes a sleek, coupe-like silhouette, differentiating it from more conventional family hatchbacks. The 2005 facelift brought subtle but noticeable changes to the front and rear fascias, including revised headlights and taillights, and a redesigned front bumper. Inside, the Signum offered a spacious and well-equipped cabin. Key features included comfortable seating, a user-friendly dashboard layout, and a range of available options such as leather upholstery, climate control, and a premium audio system. Safety features, typical for a vehicle of this era, included Anti-lock Braking System (ABS). The Signum’s focus was on providing a comfortable and refined driving experience, combined with a degree of practicality thanks to its hatchback body style and generous cargo space. The fuel tank capacity is 60 liters (15.85 US gal | 13.2 UK gal).

Technical Specifications