Opel Straight-6 engine
Encyclopedia
Opel
used the straight-6
engine configuration for many years, creating a major family of straight-6 engines for the 1970s and 1980s.
was the first Opel vehicle with a straight-6. It used a 1790 cc six in 1933. It was a 12-valve engine with a very-undersquare 65.0 mm (2.6 in) bore and 90.0 mm (3.5 in) stroke, typical for the time. This engine produced 33.5 PS (33 hp/25 kW
) and 100 N·m
(74 ft·lbf
).
was the next vehicle from the company with a straight-6 engine. This was a 2605 cc unit with 12 overhead valve
s. Bore and stroke were now oversquare for high power output at 85.0 mm (3.3 in) by 76.5 mm (3 in). A single Opel-designed carburetor
and 7.8:1 compression
yielded 91 PS (90 hp/67 kW) and 186 N·m (137 ft·lbf).
cars. It was displaced by the Opel-designed 54° V6
in the mid 1990s.
These engines were cam in head
cam chain driven, units with carburetor
s in the 1960s and 1970s,
but was later fitted with Bosch fuel injection
in the early 1980s.
A special 24v head design appeared on the Carlton/Omega and Senator in the beginning of the 1990s,
this was later turbocharged by Lotus for the 1990s Lotus Omega/Carlton
.
. Still a 12-valve engine, it had a very oversquare 87.0 mm (3.4 in) bore and 69.8 mm (2.7 in) stroke. 9.5:1 compression and a single carburettor produced 117 PS (115 hp/86 kW) and 174 N·m (128 ft·lbf), while 9.0:1 compression and dual carbs produced 132 PS (130 hp/97 kW) and 186 N·m (137 ft·lbf).
, VR
, and VS Commodores
between circa 1992 and 1997. These cars were usually labelled "Opel Calais".
The carburated version can also be found in the Monza and Senator,
wile the second Commodore also had a fuelinjected version produsing 150 PS
The carburated version had 150 hp, while in the more popular fuel injected version, the 3.0 produced 181 PS (178 hp/132 kW) and 248 N·m (183 ft·lbf) in the Opel Monza GSE and Opel Senator
3.0E.
Bore was up to 95.0 mm (3.7 in), but stroke remained at 69.8 mm (2.7 in).
The 1986 Opel Omega
3000 / Vauxhall Carlton GSi introduced the latest version of the 3.0.
The injected engine produced 180 PS (177 hp/132 kW) and 240 N·m (177 ft·lbf).
Amongst the chages were larger valves and the change to Bosch Motronic.
It was later used in the Senator and Omega 3.0i.
In 1989, a DOHC 24 valve version with a variable length intake manifold
was introduced, with power increasing to 204 PS (150 kW) and 270 N·m.
The Omega Evo had a special Irmscher version of the 24v with an uprated head,
forged internals producing 230 PS
Later, they fitted it with the 24v DOHC head,
and put the engine in special Irmscher versions of the Omega A/Carlton and Senator B models.
The Irmscher version was put in the Omega Evo models, producing 272 PS
introduced a stroked (to 85.0 mm (3.3 in)) version of the engine displacing 3615 cc. Lotus used twin Garrett
T25 turbocharger
s and an air-to-water intercooler
along with 8.2:1 compression and custom fuel injection. The turbos were arranged in parallel, each fed by and feeding three cylinders. The company reportedly experimented with a variety of forced induction
schemes, including paired supercharging
and turbocharging and sequential turbos, before settling on two small turbos for quick spool-up. The Lotus engine produced 382 PS (377 hp/281 kW) at 5200 rpm and 568 N·m (419 ft·lbf) at 4200 rpm.
Opel
Adam Opel AG, generally shortened to Opel, is a German automobile company founded by Adam Opel in 1862. Opel has been building automobiles since 1899, and became an Aktiengesellschaft in 1929...
used the straight-6
Straight-6
The straight-six engine or inline-six engine is a six-cylinder internal combustion engine with all six cylinders mounted in a straight line along the crankcase...
engine configuration for many years, creating a major family of straight-6 engines for the 1970s and 1980s.
Moonlight
The Opel Moonlight roadsterRoadster
A roadster is a two-seat open car with emphasis on sporty handling and without a fixed roof or side weather protection. Strictly speaking a roadster with wind-up windows is a convertible but as true roadsters are no longer made the distinction is now irrelevant...
was the first Opel vehicle with a straight-6. It used a 1790 cc six in 1933. It was a 12-valve engine with a very-undersquare 65.0 mm (2.6 in) bore and 90.0 mm (3.5 in) stroke, typical for the time. This engine produced 33.5 PS (33 hp/25 kW
Watt
The watt is a derived unit of power in the International System of Units , named after the Scottish engineer James Watt . The unit, defined as one joule per second, measures the rate of energy conversion.-Definition:...
) and 100 N·m
Newton metre
A newton metre is a unit of torque in the SI system. The symbolic form is N m or N·m, and sometimes hyphenated newton-metre...
(74 ft·lbf
Torque
Torque, moment or moment of force , is the tendency of a force to rotate an object about an axis, fulcrum, or pivot. Just as a force is a push or a pull, a torque can be thought of as a twist....
).
Kapitän
The 1956 Opel KapitänOpel Kapitän
The Kapitän was the last new Opel model to appear before the outbreak of the Second World War, developed during 1938 and launched in the spring of 1939 at the Geneva motor show. The first Kapitän was available in many different body styles, the most popular one being the 4-door saloon. 2-door...
was the next vehicle from the company with a straight-6 engine. This was a 2605 cc unit with 12 overhead valve
Overhead valve
An overhead valve engine, also informally called pushrod engine or I-head engine, is a type of piston engine that places the camshaft within the cylinder block , and uses pushrods or rods to actuate rocker arms above the cylinder...
s. Bore and stroke were now oversquare for high power output at 85.0 mm (3.3 in) by 76.5 mm (3 in). A single Opel-designed carburetor
Carburetor
A carburetor , carburettor, or carburetter is a device that blends air and fuel for an internal combustion engine. It is sometimes shortened to carb in North America and the United Kingdom....
and 7.8:1 compression
Compression ratio
The 'compression ratio' of an internal-combustion engine or external combustion engine is a value that represents the ratio of the volume of its combustion chamber from its largest capacity to its smallest capacity...
yielded 91 PS (90 hp/67 kW) and 186 N·m (137 ft·lbf).
1968–1993
The modern (1968–1993) straight-6 was used in the largest Opel and VauxhallVauxhall Motors
Vauxhall Motors is a British automotive company owned by General Motors and headquartered in Luton. It was founded in 1857 as a pump and marine engine manufacturer, began manufacturing cars in 1903 and was acquired by GM in 1925. It has been the second-largest selling car brand in the UK for...
cars. It was displaced by the Opel-designed 54° V6
GM 54-Degree V6 engine
General Motors' Opel subsidiary in Europe designed a compact V6 engine with an odd 54° vee angle. It was an iron block/aluminum head DOHC design with 4 valves per cylinder. All 54° engines were assembled at Ellesmere Port in England....
in the mid 1990s.
These engines were cam in head
Overhead camshaft
Overhead cam valvetrain configurations place the engine camshaft within the cylinder heads, above the combustion chambers, and drive the valves or lifters in a more direct manner compared to overhead valves and pushrods...
cam chain driven, units with carburetor
Carburetor
A carburetor , carburettor, or carburetter is a device that blends air and fuel for an internal combustion engine. It is sometimes shortened to carb in North America and the United Kingdom....
s in the 1960s and 1970s,
but was later fitted with Bosch fuel injection
Fuel injection
Fuel injection is a system for admitting fuel into an internal combustion engine. It has become the primary fuel delivery system used in automotive petrol engines, having almost completely replaced carburetors in the late 1980s....
in the early 1980s.
A special 24v head design appeared on the Carlton/Omega and Senator in the beginning of the 1990s,
this was later turbocharged by Lotus for the 1990s Lotus Omega/Carlton
Lotus Carlton
The Lotus Carlton was a Vauxhall Carlton saloon upgraded by Lotus Cars to be a 177 mph sports sedan with acceleration to equal contemporary supercars. Like all Lotus vehicles, it was given a type designation — Type 104 in this case...
.
2.5
The modern Opel straight-6 line began in 1968 with the 2.5 L (2490 cc) unit used in the Opel CommodoreOpel Commodore
The Opel Commodore is an executive car produced by Opel. It is the six-cylinder variant of the Rekord with styling differences. The Commodore nameplate was used by Opel from 1967 to 1982. However, its lineage continues with the Australian Holden Commodore...
. Still a 12-valve engine, it had a very oversquare 87.0 mm (3.4 in) bore and 69.8 mm (2.7 in) stroke. 9.5:1 compression and a single carburettor produced 117 PS (115 hp/86 kW) and 174 N·m (128 ft·lbf), while 9.0:1 compression and dual carbs produced 132 PS (130 hp/97 kW) and 186 N·m (137 ft·lbf).
2.6
At the introduction of the 24v DOHC engine in Senator/Carlton/Omega, the 2.5 increased volume to 2.6 litres and with a reworked cylinderhead (still with twelve valves and pushrods) and RAM Induction it now produced 150 PS. This engine was also fitted to southeast Asian export market versions of the Holden VPHolden VP Commodore
The Holden VP Commodore is an automobile which was produced by Australian automaker Holden from 1991 to 1993. It is the seventh generation Holden Commodore....
, VR
Holden VR Commodore
The Holden VR Commodore of July 1993 came with an updated, sleeker and more modern design, as well as safety enhancements such as anti-lock brakes . From the side, the biggest change was the use of a round rear wheelarch, instead of a squared-off shape used on the previous VN and VP model Commodores...
, and VS Commodores
Holden VS Commodore
The Holden VS Commodore, released in 1995, was the ninth model of the Holden Commodore, a large car built by Holden, the Australian subsidiary of General Motors. The VS Commodore served as a mechanical update of the second generation architecture, destined to assist sales before the all-new VT model...
between circa 1992 and 1997. These cars were usually labelled "Opel Calais".
2.8
The 2.8 was introduced in the first Commodore model.The carburated version can also be found in the Monza and Senator,
wile the second Commodore also had a fuelinjected version produsing 150 PS
3.0
The 3.0 L (2969 cc) version was introduced in 1977 alongside the fuel-injected 2.5.The carburated version had 150 hp, while in the more popular fuel injected version, the 3.0 produced 181 PS (178 hp/132 kW) and 248 N·m (183 ft·lbf) in the Opel Monza GSE and Opel Senator
Opel Senator
The Opel Senator was a large automobile, two generations of which were sold in Europe by Opel, from 1978 until 1993. A saloon, its first incarnation was also available with a fastback coupé body as the Opel Monza and Vauxhall Royale Coupe....
3.0E.
Bore was up to 95.0 mm (3.7 in), but stroke remained at 69.8 mm (2.7 in).
The 1986 Opel Omega
Opel Omega
The Opel Omega was an executive car marketed by the German automaker Opel between 1986 and 2003 in two generations, both manufactured at Opel's Rüsselsheim, Germany plant. The first generation, the Omega A , superseded the Opel Rekord, was voted European Car of the Year for 1987, and was available...
3000 / Vauxhall Carlton GSi introduced the latest version of the 3.0.
The injected engine produced 180 PS (177 hp/132 kW) and 240 N·m (177 ft·lbf).
Amongst the chages were larger valves and the change to Bosch Motronic.
It was later used in the Senator and Omega 3.0i.
In 1989, a DOHC 24 valve version with a variable length intake manifold
Variable Length Intake Manifold
In internal combustion engines, a variable length intake manifold , or variable intake manifold is an automobile internal combustion engine manifold technology...
was introduced, with power increasing to 204 PS (150 kW) and 270 N·m.
The Omega Evo had a special Irmscher version of the 24v with an uprated head,
forged internals producing 230 PS
3.6
Irmscher made a 12v 3.6 engine and fitted it to the Monza.Later, they fitted it with the 24v DOHC head,
and put the engine in special Irmscher versions of the Omega A/Carlton and Senator B models.
4.0
4.0 24v DOHC versions were made both by Irmscher and Mantzel.The Irmscher version was put in the Omega Evo models, producing 272 PS
Lotus 3.6 twin turbo
The Lotus Omega/CarltonLotus Carlton
The Lotus Carlton was a Vauxhall Carlton saloon upgraded by Lotus Cars to be a 177 mph sports sedan with acceleration to equal contemporary supercars. Like all Lotus vehicles, it was given a type designation — Type 104 in this case...
introduced a stroked (to 85.0 mm (3.3 in)) version of the engine displacing 3615 cc. Lotus used twin Garrett
Garrett AiResearch
Garrett AiResearch was a manufacturer of turboprop engines and turbochargers, and a pioneer in numerous aerospace technologies. It was previously known as Aircraft Tool and Supply Company, Garrett Supply Company, AiResearch Manufacturing Company, or simply AiResearch...
T25 turbocharger
Turbocharger
A turbocharger, or turbo , from the Greek "τύρβη" is a centrifugal compressor powered by a turbine that is driven by an engine's exhaust gases. Its benefit lies with the compressor increasing the mass of air entering the engine , thereby resulting in greater performance...
s and an air-to-water intercooler
Intercooler
An intercooler , or charge air cooler, is an air-to-air or air-to-liquid heat exchange device used on turbocharged and supercharged internal combustion engines to improve their volumetric efficiency by increasing intake air charge density through nearly isobaric cooling, which removes...
along with 8.2:1 compression and custom fuel injection. The turbos were arranged in parallel, each fed by and feeding three cylinders. The company reportedly experimented with a variety of forced induction
Forced induction
Forced induction is the process of compressing air on the intake of an internal combustion engine . A forced induction engine uses a gas compressor to increase the pressure, temperature and density of the air...
schemes, including paired supercharging
Supercharger
A supercharger is an air compressor used for forced induction of an internal combustion engine.The greater mass flow-rate provides more oxygen to support combustion than would be available in a naturally aspirated engine, which allows more fuel to be burned and more work to be done per cycle,...
and turbocharging and sequential turbos, before settling on two small turbos for quick spool-up. The Lotus engine produced 382 PS (377 hp/281 kW) at 5200 rpm and 568 N·m (419 ft·lbf) at 4200 rpm.