Ford I4 DOHC engine
Encyclopedia
The Ford I4 DOHC engine was a 4-cylinder inline internal combustion engine
with twin overhead camshafts, produced by the Ford Motor Company
. First with 2.0-litre 8-valve version, in later models with 2.0/2.3-litre 16-valve version from 1989 to the end of production of the MK2 Ford Galaxy
in 2006. It powered various Ford models during this time, but was most well known in the rear wheel drive "Twin Cam" variants of the Ford Sierra
, and Ford Scorpio
. Despite being built for the company's larger RWD
models, Ford unusually employed the engine in the front wheel drive Galaxy and sport version of Escort named RS 2000 16v.
, derivatives of which had powered most of Ford's four-cylinder rear-wheel drive cars since the early 1970s, and which was now lagging badly behind the competition in terms of power output, efficiency and refinement. Equipped with a newly designed twin-cam cylinder head but still only 8 valves, and a "square" 86x86mm bore and stroke, the new I4 unit was launched in the Ford Sierra
and Ford Scorpio
, mated to the newly designed all-synchromesh MT-75 5-speed manual transmission, or the existing A4LD four-speed automatic. The engine itself received mixed reviews, being seen as an improvement over the Pinto, but not the leap forward one might have expected. However with the Sierra in its twilight years, and the new bigger Mondeo ultimately destined to replace both Sierra
and Scorpio
, and with the forthcoming Mondeo having been developed around the new Zetec unit, it is conceivable that Ford knew the engine would have a relatively short production life, and chose to keep investment costs low.
Ford's strategy was to introduce two high-performance versions to steal some of the lucrative hot hatch market, using the well known XR3i and RS2000 badges. The XR3i was to be powered by tweaked versions of the new Zetec 1.8-litre engine from the standard Escort range, but the 2.0 Zetec unit being developed for the new Mondeo was a still a year away. Rather than wait for the new engine to become available, Ford took the unusual decision to take the longitudinally mounted I4, install a highly efficient multivalve cylinder head and tubular exhaust manifold, and mount it transversely in an FWD application. Designated N7A, critics remarked on its similarity in both specification and appearance to the Astra GTE's legendary C20XE
"Redtop" unit which itself was widely regarded as the top hot hatch engine of the time. How much of this similarity was intentional is hard to say, but Ford would have to have been aware of the huge success enjoyed by the Astra, and the amount of credit its engine was given for that success. Certainly the RS2000's engine was well regarded, and is still seen as lively and characterful today.
With the disappearance of the Sierra in 1993, and the fading of the RS2000 in the mid 90's, the I4 engine went on to more workaday applications, later appearing the Ford Galaxy
MPV, launched in 1995 as the result of a collaboration with Volkswagen/Seat. By this time, a bored out 2.3-litre 16-valve version of the engine was available alongside the original 2.0 which was still available in both 8-valve and 16-valve versions. This 2.3-litre unit also found its way into the Ford Scorpio
and the Ford Transit
van.
Internal combustion engine
The internal combustion engine is an engine in which the combustion of a fuel occurs with an oxidizer in a combustion chamber. In an internal combustion engine, the expansion of the high-temperature and high -pressure gases produced by combustion apply direct force to some component of the engine...
with twin overhead camshafts, produced by the Ford Motor Company
Ford Motor Company
Ford Motor Company is an American multinational automaker based in Dearborn, Michigan, a suburb of Detroit. The automaker was founded by Henry Ford and incorporated on June 16, 1903. In addition to the Ford and Lincoln brands, Ford also owns a small stake in Mazda in Japan and Aston Martin in the UK...
. First with 2.0-litre 8-valve version, in later models with 2.0/2.3-litre 16-valve version from 1989 to the end of production of the MK2 Ford Galaxy
Ford Galaxy
The first Galaxy was designed as a joint venture product between Ford and the Volkswagen Group. Produced at the joint-venture AutoEuropa plant in Palmela, Portugal, the vehicle was badge-engineered to create three vehicles: the Ford Galaxy; by Volkswagen Passenger Cars as the Volkswagen Sharan;...
in 2006. It powered various Ford models during this time, but was most well known in the rear wheel drive "Twin Cam" variants of the Ford Sierra
Ford Sierra
The Ford Sierra is a large family car that was built by Ford Europe from 1982 until 1993. It was designed by Uwe Bahnsen, Robert Lutz and Patrick le Quément. The code used during development was "Project Toni"....
, and Ford Scorpio
Ford Scorpio
The Ford Scorpio is an automobile that was produced by the Ford Motor Company from 1985 through to 1998.It was the replacement for the European Ford Granada line...
. Despite being built for the company's larger RWD
RWD
RWD may refer to:* Rear-wheel drive, method of propulsion in an automobile* RWD , Polish aircraft manufacturer* RWD Technologies, software vendor of electronic performance support systems* Rewind Magazine, British based music magazine...
models, Ford unusually employed the engine in the front wheel drive Galaxy and sport version of Escort named RS 2000 16v.
History
The I4 was originally designed to replace the ageing 2.0L OHC Pinto engineFord Pinto engine
The Ford Pinto engine was the unofficial but generic nickname for a 4-cylinder internal combustion engine built by Ford Europe. In Ford sales literature it was referred to as the EAO or OHC engine and because it was designed to the metric system, it was sometimes called the "Metric engine". The...
, derivatives of which had powered most of Ford's four-cylinder rear-wheel drive cars since the early 1970s, and which was now lagging badly behind the competition in terms of power output, efficiency and refinement. Equipped with a newly designed twin-cam cylinder head but still only 8 valves, and a "square" 86x86mm bore and stroke, the new I4 unit was launched in the Ford Sierra
Ford Sierra
The Ford Sierra is a large family car that was built by Ford Europe from 1982 until 1993. It was designed by Uwe Bahnsen, Robert Lutz and Patrick le Quément. The code used during development was "Project Toni"....
and Ford Scorpio
Ford Scorpio
The Ford Scorpio is an automobile that was produced by the Ford Motor Company from 1985 through to 1998.It was the replacement for the European Ford Granada line...
, mated to the newly designed all-synchromesh MT-75 5-speed manual transmission, or the existing A4LD four-speed automatic. The engine itself received mixed reviews, being seen as an improvement over the Pinto, but not the leap forward one might have expected. However with the Sierra in its twilight years, and the new bigger Mondeo ultimately destined to replace both Sierra
Ford Sierra
The Ford Sierra is a large family car that was built by Ford Europe from 1982 until 1993. It was designed by Uwe Bahnsen, Robert Lutz and Patrick le Quément. The code used during development was "Project Toni"....
and Scorpio
Scorpio
-Technology:* Scorpio , Roman artillery invented in 50 BC* Scorpio ROV, a class of submersible remotely operated vehicle, including the Scorpio II and Super Scorpio operated by the US and UK navies* Mahindra Scorpio, an Indian SUV...
, and with the forthcoming Mondeo having been developed around the new Zetec unit, it is conceivable that Ford knew the engine would have a relatively short production life, and chose to keep investment costs low.
Transverse installation
Although front wheel drive, and powered by a separate range of transversely mounted engines, the smaller Escort model was to play host to the next major incarnation of the I4. In 1990, the mkV Escort had been launched to disappointing press reviews, and Ford were looking to boost the image of this critically important range and steal sales from arch rivals Vauxhall and VW who were doing very well with big bore GTE/GTI badged versions of their family hatches.Ford's strategy was to introduce two high-performance versions to steal some of the lucrative hot hatch market, using the well known XR3i and RS2000 badges. The XR3i was to be powered by tweaked versions of the new Zetec 1.8-litre engine from the standard Escort range, but the 2.0 Zetec unit being developed for the new Mondeo was a still a year away. Rather than wait for the new engine to become available, Ford took the unusual decision to take the longitudinally mounted I4, install a highly efficient multivalve cylinder head and tubular exhaust manifold, and mount it transversely in an FWD application. Designated N7A, critics remarked on its similarity in both specification and appearance to the Astra GTE's legendary C20XE
C20XE
The C20XE is a DOHC, inline 4 cylinder Family II, Opel engine. It has a displacement of and develops .The C20XE came into production as an evolution of the C20NE engine. It was a further development of the 1987 model 8v 20NE engine...
"Redtop" unit which itself was widely regarded as the top hot hatch engine of the time. How much of this similarity was intentional is hard to say, but Ford would have to have been aware of the huge success enjoyed by the Astra, and the amount of credit its engine was given for that success. Certainly the RS2000's engine was well regarded, and is still seen as lively and characterful today.
With the disappearance of the Sierra in 1993, and the fading of the RS2000 in the mid 90's, the I4 engine went on to more workaday applications, later appearing the Ford Galaxy
Ford Galaxy
The first Galaxy was designed as a joint venture product between Ford and the Volkswagen Group. Produced at the joint-venture AutoEuropa plant in Palmela, Portugal, the vehicle was badge-engineered to create three vehicles: the Ford Galaxy; by Volkswagen Passenger Cars as the Volkswagen Sharan;...
MPV, launched in 1995 as the result of a collaboration with Volkswagen/Seat. By this time, a bored out 2.3-litre 16-valve version of the engine was available alongside the original 2.0 which was still available in both 8-valve and 16-valve versions. This 2.3-litre unit also found its way into the Ford Scorpio
Ford Scorpio
The Ford Scorpio is an automobile that was produced by the Ford Motor Company from 1985 through to 1998.It was the replacement for the European Ford Granada line...
and the Ford Transit
Ford Transit
The Ford Transit is a range of panel vans, minibuses, and pickup trucks, produced by the Ford Motor Company in Europe.The Transit has been the best-selling light commercial vehicle in Europe for 40 years, and in some countries the term "Transit" has passed into common usage as a generic term...
van.
8v engine Specifications
- Two valvePoppet valveA poppet valve is a valve consisting of a hole, usually round or oval, and a tapered plug, usually a disk shape on the end of a shaft also called a valve stem. The shaft guides the plug portion by sliding through a valve guide...
s per cylinder with hydraulic valve lifters - Twin camshaftCamshaftA camshaft is a shaft to which a cam is fastened or of which a cam forms an integral part.-History:An early cam was built into Hellenistic water-driven automata from the 3rd century BC. The camshaft was later described in Iraq by Al-Jazari in 1206. He employed it as part of his automata,...
s driving by a timing chainTiming beltA timing belt, or cam belt , is a part of an internal combustion engine that controls the timing of the engine's valves. Some engines, such as the flat-4 Volkswagen air-cooled engine, and the straight-6 Toyota F engine use timing gears... - Stroke and bore were both 86 mm (3.4 in)
- Compression was 10.3:1 (Later versions of the 8V DOHC were 9.8:1)
- Five main crankshaftCrankshaftThe crankshaft, sometimes casually abbreviated to crank, is the part of an engine which translates reciprocating linear piston motion into rotation...
bearings
N8A
- Carbureted
- Power: 107 hp (80 kW) at 5600 rpm.
- Torque: 174 newton metre at 3000 rpm.
- Redline: 6050 rpm
N9A
- Electronic fuel injection (Batched multi-point)
- Power: 123 hp (92 kW) at 5500 rpm.
- Torque: 174 newton metre at 2500 rpm.
- Redline: 5950 rpm
N9C/N9E/NSE/N9D
- Electronic fuel injection (Batched multi-point)
- Catalytic converterCatalytic converterA catalytic converter is a device used to convert toxic exhaust emissions from an internal combustion engine into non-toxic substances. Inside a catalytic converter, a catalyst stimulates a chemical reaction in which noxious byproducts of combustion are converted to less toxic substances by dint...
- Power: 118 hp (88 kW) at 5500 rpm
- Torque: 171 newton metre at 2500 rpm.
- Redline: 5950 rpm
N7A
- Capacity: 1998 cc
- Bore: 86.0 mm
- Stroke: 86.0 mm
- Compression: 10.3:1
- Valvegear: Chain driven twin OHC. 16 valves. Hydraulic tappets.
- Fuelling: EEC-IV controlled multi-point fuel injection
- Power: 150 hp @ 6000 rpm
- Torque: 190 newton metre @ 4500 rpm
N3A
- Capacity: 1998 cc
- Bore: 86.0 mm
- Stroke: 86.0 mm
- Compression: 9.8:1
- Valvegear: Chain driven twin OHC. 16 valves. Hydraulic tappets.
- Fuelling: EEC-V controlled multi-point fuel injection
- Power: 136 hp @ 6300 rpm
- Torque: 175 newton metre @ 4200 rpm
Y5A/Y5B
- Capacity: 2295 cc
- Bore: 89.6 mm
- Stroke: 91.0 mm
- Compression: 10:1
- Valvegear: Chain driven twin OHC. 16 valves. Hydraulic tappets.
- Fuelling: EEC-V controlled multi-point fuel injection
- Power: 145 hp @ 5600 rpm
- Torque: 210 newton metre @ 4500 rpm
See also
- List of Ford engines
- Ford SierraFord SierraThe Ford Sierra is a large family car that was built by Ford Europe from 1982 until 1993. It was designed by Uwe Bahnsen, Robert Lutz and Patrick le Quément. The code used during development was "Project Toni"....
- Ford ScorpioFord ScorpioThe Ford Scorpio is an automobile that was produced by the Ford Motor Company from 1985 through to 1998.It was the replacement for the European Ford Granada line...