The C20XE came into production as an evolution of the 20XE engine. Incidentally, the 20XE engine was a further development of the 1987 model 8v 20NE engine. The 20XE(Bosh Motronic ML 4.1) first saw the light of day in 1987 with the launch of the Opel Kadett GSI 16v, introducing 16 valve technology and Knock Sensors to Opel/Vauxhall lineup. In 1988 the C20XE was introduced, with a 150 hp output compared to the earlier 20XE's 157 hp. This was due to new emission standards, which forced manufacturers to specify their cars with a catalytic converter and a lambda sensor - this requirement permitted the fitment of a new generation of Engine Management Systems(Bosch Motronic 2.5).
The C20XE engine featured in many General Motors vehicles including some models of the Vauxhall/Opel Astra/Kadett E and the Vauxhall/Opel Calibra/Cavalier/Vectra. Enthusiasts commonly refer to this engine as the 'Red Top' (or just 'XE') because of its distinct appearance. At the time of its launch, this engine was something of a milestone unit in Europe and was widely used in motorsport in many specialist race versions. It is still revered and sought after by enthusiasts today some 18 years later. A version of the engine also appeared in Lada cars in the late 1990s.
The C20XE served as the base for the turbocharged C20LET, which appeared in versions of the Vauxhall Cavalier/Opel Vectra and the Vauxhall/Opel Calibra. The C20LET was identical on the surface, apart from a black plastic plenum/'top hat' shroud with a 'turbo' script. This version features forged, lower compression Mahle pistons, and offers a 34% increase of power (204 PS) over the C20XE.
Some versions of the engine implemented switchable Traction Control (commonly included in the early Astra GSi models). The inlet had a secondary throttle valve sandwiched underneath the primary throttle body. This is closed by a motor/arm assembly when the traction control ECU senses loss of grip/spin at the wheels. The engine was also equipped with a different Throttle Position Sensor (six pin, as opposed to three), and a different Coolant Temperature Sensor (which was black, as opposed to the normal light blue colour).
In its last version before production ended, the C20XE came with a new engine management system which included a distributorless ignition system, namely Bosch Motronic 2.8. The last version was called C20LN (Low Noise) and has a stronger engine block.
The 20XE has now evolved into a large family of GM 16v engines, one of which is a 2.2L 16v chain driven engine found in many GM brands, including Saab, Pontiac, Saturn, Chevrolet, Oldsmobile. It was borrowed to Fiat and Alfa Romeo, for the Croma and the 159 respectively.
All of the 2 litre engine of this era share the same cast iron engine block with the exception of the oil return for the turbo on the C20LET.
Since an engine's oil pressure is much higher than its coolant pressure, oil in a porus head has a tendency to gradually seep into the cooling galleries. A typical symptom of a porous head is usually a 'mayonnaise'-like substance in the coolant (residing on the cap). However, symptoms of a porous head have a tendency to vary, depending on the degree of porosity. Many C20XE operators have described the symptom as a curry-like residue or in more severe cases, a thick brown sludge. During the porous head debarcle, GM faced bankruptcy - therefore dealers failed to recall affected models. However, as a result, many businesses now specialise in the repair of porous GM C20XE/LET heads - by either sleeving the affected gallery or by injecting a polymer based substance into the porous region. Typically, the amount of cylinder heads that were reportedly porous remained relatively low.
The early engines used round tooth cambelts, the later used square (with a plastic pre-tensioner). There are also subtle differences between the crankshaft, and visible difference in the pattern of the SFi airbox.
The engine produces at 6,000 rpm, with a low optimum specific fuel consumption of 232 g/kWh which is equivalent to a maximum efficiency of 37 per cent; a better efficiency than some of the diesel engines that were available at the time of its release. The valves are set at 46 degrees and are accompanied by pistons with shallow valve pockets - thereby eliminating the need for a shorter con rod hence, allowing a suitable compression ratio to be achieved. Long spark plugs are used and positioned concentric to the cylinder. Incidentally, the engine has a square bore/stroke and shares piston dimensions with the Bugatti Veyron (86mm x 86mm).
|No Of Cylinders||4|
|Displacement||1998cc (121.88 cu in)|
|Torque Nm/rpm||196 (133 lb ft)/4800|
|Engine management||Bosch Motronic 2.5/Bosch Motronic 2.8|
|Opel Calibra 16V||1989-1994||Europe, Australia|
|Opel Kadett E, GSI/GTE||1988-1992||Europe - Germany, Ireland|
|Opel Vectra A, GTE||1988-1995||Europe, New Zealand|
|Opel Astra F||1991 - 1994||Europe, Australia|
|Vauxhall Calibra 16V||1989-1994||UK|
|Vauxhall Astra Mk 2, GTE||1988-1992||UK|
|Vauxhall Cavalier Mk 3, GSi, SRi||1988-1995||UK|
|Vauxhall Astra Mk 3, GSi||1991 - 1994||UK|
|Lada 110||1996 -||Europe, Russia|
|Chevrolet Vectra GSi||1993 - 1996||Brazil|