The Ford Sigma is a small straight four

automobile A car, or an automobile, is a motor vehicle with wheels. Most definitions of cars state that they run primarily on roads, Car seat, seat one to eight people, have four wheels, and mainly transport private transport#Personal transport, peopl ...

engine An engine or motor is a machine designed to convert one or more forms of energy into mechanical energy. Available energy sources include potential energy (e.g. energy of the Earth's gravitational field as exploited in hydroelectric power ge ...

introduced in 1995 by

Ford Motor Company Ford Motor Company (commonly known as Ford) is an American multinational corporation, multinational automobile manufacturer headquartered in Dearborn, Michigan, United States. It was founded by Henry Ford and incorporated on June 16, 1903. T ...

. Its first evolution was sold as the Zetec-S (not to be confused with the trim level), then Zetec-SE and finally, in later years, renamed Duratec. The last upgrade of the engine is named Duratec Ti-VCT. Conceived for Ford's smaller models, the motor was intended to replace the older HCS (a derivative of the even older

Kent Kent is a Ceremonial counties of England, ceremonial county in South East England. It is bordered by Essex across the Thames Estuary to the north, the Strait of Dover to the south-east, East Sussex to the south-west, Surrey to the west, and Gr ...

unit) and smaller capacity CVH units.

Introduction and production

As with the SHO V6 engine, development of the Zetec-S was a collaborative effort between Ford,

Mazda is a Japanese Multinational corporation, multinational automotive manufacturer headquartered in Fuchū, Hiroshima (town), Fuchū, Hiroshima Prefecture, Hiroshima, Japan. The company was founded on January 30, 1920, as Toyo Cork Kogyo Co., Ltd. ...

and Yamaha. The engine's sound profile was refined in Ford's acoustics center in Cologne-Merkenich,

Germany Germany, officially the Federal Republic of Germany, is a country in Central Europe. It lies between the Baltic Sea and the North Sea to the north and the Alps to the south. Its sixteen States of Germany, constituent states have a total popu ...

. Production of the Zetec-SE was carried out in the Ford Valencia Engine Plant, with Yamaha building the 1.7 L engine blocks in Japan. When the Zetec-SE debuted in 1995, it included many firsts, including a plastic inlet manifold, a "ladder" style

main bearing A main bearing is a bearing in a piston engine which holds the crankshaft in place and allows it to rotate within the engine block. The number of main bearings per engine varies between engines, often in accordance with the forces produced b ...

and

crankcase A crankcase is the housing in a reciprocating engine, piston engine that surrounds the crankshaft. In most modern engines, the crankcase is integrated into the engine block. Two-stroke engines typically use a crankcase-compression design, res ...

assembly, and big-end bearing caps which are forged in one piece and subsequently split. It also incorporates powder metal

connecting rod A connecting rod, also called a 'con rod', is the part of a reciprocating engine, piston engine which connects the piston to the crankshaft. Together with the crank (mechanism), crank, the connecting rod converts the reciprocating motion of the p ...

s, which were quite exotic at the time. This feature makes the engine more challenging to rebuild at the end of its working life, since it is not possible to re-machine the bearing ladder as is done with a conventional cylinder block — the entire assembly has to be renewed. Despite this, engine tuners have found novel ways to increase the power of the unit through use of different valves and increasing the compression ratio of the engine through skimming of the cylinder head. The engine first appeared in the Mk4 Ford Fiesta and the virtually identical Mazda 121 in capacity, with , and derivatives coming later.

Difference between Zetec-SE/Zetec-S/Duratec/Duratec Ti-VCT

File:Zetec SE 125 1.jpg, 1.25-litre Duratec engine in a 2009

Ford Fiesta The Ford Fiesta is a supermini car that was marketed by Ford from 1976 to 2023 over seven generations. Over the years, the Fiesta has mainly been developed and manufactured by Ford's European operations, and had been positioned below the ...

File:Ford Zetec-S 1.7 engine.JPG, 1.7-litre Zetec-S engine in a Ford Puma File:Zetec SE 16 1.jpg, 1.6-litre Duratec engine with TI-VCT in a 2012

Ford Focus The Ford Focus is a compact car (C-segment in Europe) manufactured by Ford Motor Company from 1998 until 2025. It was created under Alexander Trotman's Ford 2000 plan, which aimed to globalize model development and sell one compact vehicle worl ...

The Sigma engine was introduced under the Zetec-S name; after the upgrade it was renamed to Zetec-SE, Duratec and Duratec Ti-VCT. The latest upgrade of Sigma is called Ecoboost 1.6 engine (Not to be confused with the smaller 1.0 or larger 2.0/2.3 engines)

Zetec-S/SE

Zetec-S

The engines uses a heavily modified 1.4 L engine block and features

Variable Cam Timing Variable camshaft timing (VCT) is an Car, automobile variable valve timing technology developed by Ford Motor Company, Ford. It allows for more optimum engine performance, reduced emissions, and increased fuel efficiency compared to engines with f ...

on the inlet camshaft. This displacement has only been used in the Ford Puma. A version of this engine was developed for the Ford Racing Puma with only 500 units built.

Zetec RoCam

In 2000, Ford of

Brazil Brazil, officially the Federative Republic of Brazil, is the largest country in South America. It is the world's List of countries and dependencies by area, fifth-largest country by area and the List of countries and dependencies by population ...

developed a cheaper version of the Zetec-SE engine, to compete with the classic

Volkswagen EA827 engine The EA827 family of petrol engines was initially developed by Audi under Ludwig Kraus leadership and introduced in 1972 by the B1-series Audi 80, and went on to power many Volkswagen Group models, with later derivatives of the engine still in prod ...

series known locally as (from ''Alta Performance'', "High Performance" in English) engine in Brazil. It is 8v

SOHC An overhead camshaft (OHC) engine is a piston engine in which the camshaft is located in the cylinder head above the combustion chamber. This contrasts with earlier overhead valve engines (OHV), where the camshaft is located below the combus ...

instead of 16v

DOHC An overhead camshaft (OHC) engine is a piston engine in which the camshaft is located in the cylinder head above the combustion chamber. This contrasts with earlier overhead valve engines (OHV), where the camshaft is located below the combus ...

and its block is made of cast iron instead of aluminum. Also, its camshaft is driven by a chain instead of a belt. As a result this engine exhibits rougher behaviour, producing more vibration and noise. On the other hand, it has a superb torque output thanks to the addition of the RoCam (Rollifinger Camshaft) feature. It's also a much smaller engine than the SE version, which allowed it to be installed on the

Ford Ka The Ford Ka is a small car manufactured by Ford Motor Company from 1996 to 2016 as a city car and from 2014 to 2021 as a subcompact car. It entered its second generation in 2008, produced by Fiat in Tychy, Poland. A third generation was introduced ...

, replacing the Endura-E engine which by that time was considered underpowered and outdated. The engine also featured a new patented process for the aluminum

head A head is the part of an organism which usually includes the ears, brain, forehead, cheeks, chin, eyes, nose, and mouth, each of which aid in various sensory functions such as sight, hearing, smell, and taste. Some very simple ani ...

production, which resulted in a better alloy than those produced in Spain and UK, and at a lower production cost. In 2002 a

supercharged In an internal combustion engine, a supercharger compresses the intake gas, forcing more air into the engine in order to produce more power for a given displacement. It is a form of forced induction that is mechanically powered (usually by ...

1.0-litre version was released for the

, to compete with the 1.0 Turbo 16v version of the

Volkswagen Gol The Volkswagen Gol is a subcompact car that was manufactured by Volkswagen do Brasil from 1980 to 2023 as Volkswagen's entry-level car in the Latin American market—where it succeeded the Volkswagen Type 1 (Fusca) and the Volkswagen Bra ...

. In 2001 the Zetec RoCam engine was introduced in Europe, but labeled as Duratec 8v, for the Ka and Fiesta. Later a 1.6-litre version was also released for the SportKa and StreetKa. The European versions of the engine are produced in the South Africa plant. In October/2004 a newer bi-fuel version was introduced labeled "1.6 L Flex", capable of running on both petrol and

ethanol Ethanol (also called ethyl alcohol, grain alcohol, drinking alcohol, or simply alcohol) is an organic compound with the chemical formula . It is an Alcohol (chemistry), alcohol, with its formula also written as , or EtOH, where Et is the ps ...

, even mixed at any proportion. This version also featured a high compression ratio of 12.3:1 and "Compound High Turbulence" chambers, as used on the CHT engine. The 1.0 L Flex runs with a compression of 12.8:1. Currently, this engine powers nearly all Brazilian Ford models – except those with 2.0 litre engines – in many different variants: * 101/106 hp 1.6 L Flex (

) * 71/73 hp 1.0 L Flex (

), 69/73 hp 1.0 L Flex after 2012 in Brazil * 105/111 hp 1.6 L Flex (

/ Fiesta Sedan), (

), Ford EcoSport)

Applications

applications: * 2003—2008 Ford SportKa 1.6, and * 2003—2006 Ford StreetKa 1.6, and

Duratec

After an upgrade to the Sigma, Ford renamed it the Duratec.

Duratec Ti-VCT

The Ti-VCT ( Twin independent Variable Camshaft Timing) version includes

variable valve timing Variable valve timing (VVT) is the process of altering the timing of a Poppet valve, valve lift event in an internal combustion engine, and is often used to improve performance, fuel economy or emissions. It is increasingly being used in combina ...

, and generates more power and torque than non-VVT counterparts. Latest versions comply with the Euro5 emission level.

Crate engine versions

Crate engine versions of Zetec-SE engines are sold by Ford Power Products under the name ZSG Range.

Applications

Current use

The Ford Sigma engine was produced at Bridgend Ford in Wales, U.K. until September 2020 and at Taubate Engine and Transmission Plant, Taubate, São Paulo, Brazil. Today the Sigma engine is used as the basis for the four cylinder Ford Ecoboost 1.5 litre and 1.6 litre engines. A version was used by Morgan for their 4/4 Roadster coupled to a Mazda transmission from 2009 until the model was discontinued in 2018.

1.25/1.4/1.6 L Sigma

These engines in the first generation Focus produced 75 and respectively, but for MkII Focus the 1.4 variant was slightly modified and produced . Both engines have belt driven camshafts and Electronic Fuel Injection systems. They weigh . The 1.6 Ti-VCT was introduced in 2004, it features Variable Cam Timing; this version is used in MkII Focus. A new or EU5 version is used in the MkIII Focus, also a 1.6 L version is used in Ford Fiesta Zetec-S. The Sigma is usually coupled to the Ford IB5 five-speed

manual transmission A manual transmission (MT), also known as manual gearbox, standard transmission (in Canadian English, Canada, British English, the United Kingdom and American English, the United States), or stick shift (in the United States), is a multi-speed ...

Brazil

Recently the Sigma engine was present in modern Brazilian versions of the Fiesta, Focus and Ecosport (1.6 L TI-VCT version) and a 1.5 version was used by Ka. This engine was able to use the flex technology. Power with ethanol: * 1.5 L Sigma (non TI-VCT) — IB5+ manual transmission ** Fiesta (2014–2016) — ** Ka (2014–2021) — * 1.6 Sigma (non TI-VCT) — IB5+ manual transmission (both) and PowerShift (Fiesta Only). ** Fiesta (2008–2014) — ** Ecosport (2012–2023) — * 1.6 Sigma TI-VCT — IB5+ manual transmission and PowerShift. ** Focus (2013–2019) — ** Fiesta (2008–2014) — ** Ecosport (2012–2023) — *In 2018 the Sigma engine was replaced in all Ford compact/subcompact cars to the newer and stronger "Dragon" engine, displacing 1.5 L with a 3-Cylinder layout and with a power output of 136HP.

Caterham usage

Some

Caterham Cars Caterham Cars Ltd. is a British manufacturer of specialist lightweight sports cars established in Caterham, England, with their headquarters in Dartford, England. Their current model, the Caterham 7 (or Seven), originally launched in 1973, is ...

use modified Ford Sigma engines such as the Caterham Seven 270, which uses a tuned Sigma engine producing at 6,800 rpm as a modern equivalent to the original Ford Kent Crossflow engine used in the Lotus 7 from 1957 to 1972.
Ford Sigma 1.6-litre overview Technical features: * a high level of running refinement and low emission levels * aluminium alloy cylinder block and head * cross flow cylinder head * structural aluminium oil-pan for increased engine stiffness * individual throttle bodies in place of the standard intake manifold * twin overhead camshafts each with five bearings * sequential multi-port fuel injection system * long life,

glass fibre Glass fiber ( or glass fibre) is a material consisting of numerous extremely fine fibers of glass. Glassmakers throughout history have experimented with glass fibers, but mass manufacture of glass fiber was only made possible with the inventio ...

reinforced camshaft drive belt with automatic tensioner * state-of-the-art Twin Independent Variable Camshaft Timing (on Ti-VCT variant)

SCCA Spec Racer

The third generation of the

SCCA The Sports Car Club of America (SCCA) is a non-profit American automobile club and sanctioning body supporting Autocross, Rallycross, High Performance Driver Education, HPDE, Time trial, Time Trial, Road racing, Road Racing, Regularity rally, R ...

Spec Racer, commonly known as the Gen3 was introduced in 2015, and uses the 1.6 L Sigma engine. The engine is sold by SCCA Enterprises as a sealed unit.

Zetec-E comparison

The Zetec-SE has no common parts or design with the larger Zetec-E engines apart from the name. This gives rise to some confusion since it suggests that they are members of the same family when they are, in fact, completely different. Zetec-E units are mounted transversely with the

inlet manifold An inlet manifold or intake manifold (in American English) is the part of an internal combustion engine that supplies the fuel/ air mixture to the cylinders. The word ''manifold'' comes from the Old English word ''manigfeald'' (from the Anglo- ...

at the rear, whereas the Zetec-SE units are mounted with the inlet manifold at the front.

Replacement

In 2012 Ford replaced the Sigma engine with a brand new 3-cylinder 1.0-litre

EcoBoost EcoBoost is a series of Turbocharger, turbocharged, petrol direct injection, direct-injection gasoline engines produced by Ford Motor Company, Ford and originally co-developed by FEV Inc. (now FEV North America Inc.). EcoBoost engines are desi ...

engine for some markets and models. The new engine provides more power and torque with less

fuel consumption A fuel is any material that can be made to react with other substances so that it releases energy as thermal energy or to be used for work. The concept was originally applied solely to those materials capable of releasing chemical energy but ...

and lower emissions.Ecoboost replaces Duratec
themotorreport.com.au, 05. February 2012.

References

External links

* {{DEFAULTSORT:Ford Sigma Engine

Sigma Sigma ( ; uppercase Σ, lowercase σ, lowercase in word-final position ς; ) is the eighteenth letter of the Greek alphabet. In the system of Greek numerals, it has a value of 200. In general mathematics, uppercase Σ is used as an operator ...

Gasoline engines by model Straight-four engines

Introduction and production

Difference between Zetec-SE/Zetec-S/Duratec/Duratec Ti-VCT

Zetec-S/SE

Zetec-S

Zetec RoCam

Applications

Duratec

Duratec Ti-VCT

Crate engine versions

Applications

Current use

1.25/1.4/1.6 L Sigma

Brazil

Caterham usage

SCCA Spec Racer

Zetec-E comparison

Replacement

See also

References

External links