The Opel Omega B (facelift, introduced in 1999) 2.5i V6 represented a premium offering within the Omega B range, produced from October 1999 to February 2000. Positioned as a flagship sedan, it aimed to provide a blend of performance, comfort, and technology. The Omega B, built on the GM Epsilon platform (internally designated 1HX0/A3), was Opel’s executive car, intended to compete with vehicles like the Ford Scorpio and BMW 5 Series. The facelift brought revised styling, improved interior appointments, and updated engine options, including this 2.5-liter V6.
The 2.5i V6: A Premium Omega B Variant
The 2.5i V6 trim was the top-of-the-line Omega B available during its short production run after the facelift. It distinguished itself from the lower-spec models, such as those equipped with four-cylinder engines, through its significantly increased power output and more refined driving experience. While a 2.0-liter 16v and a 2.6-liter straight-six were also available, the 2.5 V6 offered the highest performance within the Omega B lineup. It catered to buyers seeking a spacious, comfortable, and relatively quick executive sedan.
Powertrain & Engine Architecture
The heart of the 2.5i V6 Omega B is the X25XE engine, a 2.5-liter (2498 cm3 or 152.44 cu. in.) naturally aspirated V6. This engine features a 60-degree V-angle, contributing to its smooth operation. It boasts a bore of 81.6 mm (3.21 in.) and a stroke of 79.6 mm (3.13 in.), resulting in a compression ratio of 10.8:1. The engine utilizes a dual overhead camshaft (DOHC) valvetrain with four valves per cylinder, optimizing airflow for increased power. Fuel delivery is managed by a multi-port manifold injection system. The X25XE is known for its robust construction and relatively straightforward maintenance, although parts availability can be a concern in some markets today.
Unlike some contemporary Opel models, the 2.5i V6 Omega B was exclusively offered with a 5-speed manual transmission. There was no automatic transmission option for this specific engine and trim combination. The manual gearbox is designed to handle the V6’s torque output effectively, providing precise gear changes. The drivetrain is rear-wheel drive, a configuration that contributes to the Omega B’s balanced handling characteristics.
Driving Characteristics
The 2.5i V6 Omega B delivers a noticeably more engaging driving experience than its four-cylinder counterparts. With 170 hp (127 kW) at 5800 rpm and 226 Nm (166.69 lb-ft) of torque at 3200 rpm, the sedan achieves a 0-100 km/h (0-62 mph) acceleration time of 9.5 seconds. Top speed is rated at 228 km/h (141.67 mph). The rear-wheel-drive layout provides a balanced feel, and the V6 engine offers a smooth and linear power delivery. The 5-speed manual transmission allows for precise control over the engine’s power band. While not a sports car, the Omega B 2.5i V6 offers ample power for comfortable highway cruising and confident overtaking maneuvers. The gear ratios are tuned for a balance between acceleration and fuel efficiency, with fifth gear designed for relaxed long-distance driving.
Equipment & Trim Levels
The 2.5i V6 Omega B came generously equipped, reflecting its position as the range-topping model. Standard features typically included power windows, power door locks, central locking, air conditioning, and an upgraded audio system. Interior upholstery was typically a high-quality cloth or leather, depending on optional packages. The dashboard featured wood trim accents, enhancing the luxurious feel. Optional extras available for the 2.5i V6 included a sunroof, heated seats, automatic climate control, and upgraded alloy wheels. Safety features such as ABS (Anti-lock Braking System) were standard.
Chassis & Braking
The Omega B’s chassis utilizes coil springs for both front and rear suspension, providing a comfortable ride quality. The front suspension is a conventional coil spring setup, while the rear suspension is also coil-sprung, contributing to the car’s stability. Braking duties are handled by ventilated discs at the front and solid discs at the rear. The ABS system enhances braking performance and control, particularly in adverse conditions. The steering system is a hydraulic power steering setup, providing a responsive and precise feel. The 2.5i V6 models typically featured slightly stiffer suspension components compared to the lower-spec models, improving handling and reducing body roll.
Market Reception & Comparison
The Opel Omega B 2.5i V6 received generally positive reviews from automotive critics. It was praised for its spacious interior, comfortable ride, and strong performance. However, some critics noted its relatively high fuel consumption and its somewhat dated design compared to newer rivals. Compared to the 2.0-liter models, the 2.5i V6 offered a significant performance upgrade, but at the cost of increased fuel consumption. The 2.6-liter straight-six offered a similar level of performance but was less common. Fuel economy figures are rated at 15.3 l/100 km (15.4 US mpg, 18.5 UK mpg, 6.5 km/l) in urban conditions, 8.3 l/100 km (28.3 US mpg, 34 UK mpg, 12 km/l) extra-urban, and 10.9 l/100 km (21.6 US mpg, 25.9 UK mpg, 9.2 km/l) combined. CO2 emissions are rated at 256 g/km.
Technical Specifications
| Brand | Opel |
| Model | Omega |
| Generation | Omega B (facelift 1999) |
| Type (Engine) | 2.5i V6 (170 Hp) |
| Start of production | October, 1999 |
| End of production | February, 2000 |
| Powertrain Architecture | Internal Combustion engine |
| Body type | Sedan |
| Seats | 5 |
| Doors | 4 |
| Fuel consumption (urban) | 15.3 l/100 km (15.4 US mpg, 18.5 UK mpg) |
| Fuel consumption (extra urban) | 8.3 l/100 km (28.3 US mpg, 34 UK mpg) |
| Fuel consumption (combined) | 10.9 l/100 km (21.6 US mpg, 25.9 UK mpg) |
| CO2 emissions | 256 g/km |
| Fuel Type | Petrol (Gasoline) |
| Acceleration 0 – 100 km/h | 9.5 sec |
| Acceleration 0 – 62 mph | 9.5 sec |
| Acceleration 0 – 60 mph | 9 sec |
| Maximum speed | 228 km/h (141.67 mph) |
| Weight-to-power ratio | 9 kg/Hp |
| Weight-to-torque ratio | 6.8 kg/Nm |
| Power | 170 Hp @ 5800 rpm |
| Torque | 226 Nm @ 3200 rpm (166.69 lb.-ft. @ 3200 rpm) |
| Engine layout | Front, Longitudinal |
| Engine Model/Code | X25XE |
| Engine displacement | 2498 cm3 (152.44 cu. in.) |
| Number of cylinders | 6 |
| Engine configuration | V-engine |
| Cylinder Bore | 81.6 mm (3.21 in.) |
| Piston Stroke | 79.6 mm (3.13 in.) |
| Compression ratio | 10.8:1 |
| Number of valves per cylinder | 4 |
| Fuel injection system | Multi-port manifold injection |
| Engine aspiration | Naturally aspirated |
| Valvetrain | DOHC |
| Engine oil capacity | 5.75 l (6.08 US qt | 5.06 UK qt) |
| Coolant capacity | 9.7 l (10.25 US qt | 8.53 UK qt) |
| Kerb Weight | 1530 kg (3373.07 lbs.) |
| Max. weight | 2120 kg (4673.8 lbs.) |
| Max load | 590 kg (1300.73 lbs.) |
| Trunk (boot) space – minimum | 530 l (18.72 cu. ft.) |
| Trunk (boot) space – maximum | 830 l (29.31 cu. ft.) |
| Fuel tank capacity | 75 l (19.81 US gal | 16.5 UK gal) |
| Length | 4898 mm (192.83 in.) |
| Width | 1785 mm (70.28 in.) |
| Height | 1455 mm (57.28 in.) |
| Wheelbase | 2730 mm (107.48 in.) |
| Front track | 1514 mm (59.61 in.) |
| Rear track | 1528 mm (60.16 in.) |
| Ride height (ground clearance) | 140 mm (5.51 in.) |
| Drag coefficient (Cd) | 0.32 |
| Drivetrain | Rear wheel drive |
| Number of gears | 5 |
| Gearbox type | Manual transmission |
Legacy
The Opel Omega B 2.5i V6, while short-lived, remains a desirable classic among Opel enthusiasts. The X25XE engine is generally considered reliable, although regular maintenance is crucial. Parts availability can be challenging, particularly for specific trim components. Today, well-maintained examples command a premium in the used car market. The Omega B’s spacious interior, comfortable ride, and strong performance continue to appeal to those seeking a classic executive sedan. Its rear-wheel-drive layout and V6 engine provide a driving experience that sets it apart from many modern vehicles.
