X25XE

The X25XE is a Family II, Opel internal combustion engine. It is a 2.5 litre V6 petrol engine. It displaces 2,498 cubic centimetres (152.4 cu in), has 24 valves and uses one timing belt driven double overhead camshafts (DOHC). It produces a Deutsches Institut für Normung (DIN) rated motive power output of 125 kilowatts (170 PS; 168 bhp) in standard form, and generates a torque turning force of 227 newton metres (167 lbf·ft).

The breakdown of the engine name is as follows:

X - Exhaust Emissions Level: 94/12/EC, stage 2
25 - 2.5 Litre displacement
X - Compression Ratio - 10.0-11.5:1
E - Mixture System - Injection

In the early 1990s, Opel identified the need for a modern, lightweight and compact power plant to replace its ageing straight-6 engine range. This engine needed to be compact, to allow its use in front-wheel drive applications, as well as rear-wheel drive cars.

The first version arrived in the Opel Vectra / Vauxhall Cavalier (both codenamed "Vectra-A") and Opel/Vauxhall Calibra in the C25XE form, and was later followed by the X25XE in the Opel/Vauxhall Omega and Vectra-B, with the Omega gaining a variant with increased displacement in the form of the X30XE.

This power plant was a modern 4 valves per cylinder, quad cam arrangement, with an oil to water heat exchanger mounted within the V of the engine block. The cylinder heads were constructed from cast aluminium alloy, and the block from cast iron.

An unusual feature of the engine was its 54 degree cylinder bank angle, as opposed to the more conventional 60 degree setup used on many V6 units, this added to the setups' compactness.

A Bosch Motronic engine management system is used to control the unit, with full sequential fuel injection, knock control on each bank, distributorless ignition system (DIS), and closed loop lambda control.