Editing Ford CVH engine

{{refimprove|date=December 2009}}
{{Infobox automobile engine
| name          = Ford CVH engine
| image         = Ford_CVH_1600i_engine.jpg
| caption       = 1.6&nbsp;L Ford CVH engine in a 1988 Ford Escort XR3i
| manufacturer  = [[Ford Motor Company]]
| aka           = 
| production    = 1980–2004
| predecessor   = 
| successor     = [[Ford Zeta engine]]
| configuration = [[Inline-four engine|Inline-4]]
| displacement  = {{ubl | {{cvt|1117|cc|L cuin|1|order=flip|abbr=on}} | {{cvt|1296|cc|L cuin|1|order=flip|abbr=on}} | {{cvt|1392|cc|L cuin|1|order=flip|abbr=on}} | {{cvt|1596|cc|L cuin|1|order=flip|abbr=on}} | {{cvt|1769|cc|L cuin|1|order=flip|abbr=on}} | {{cvt|1859|cc|L cuin|1|order=flip|abbr=on}} | {{cvt|1988|cc|L cuin|1|order=flip|abbr=on}} }}
| bore          = {{ubl | {{cvt|74|mm|in|2|abbr=on}} | {{cvt|77.2|mm|in|2|abbr=on}} | {{cvt|80|mm|in|2|abbr=on}} | {{cvt|82|mm|in|2|abbr=on}} | {{cvt|84.8|mm|in|2|abbr=on}} }}
| stroke        = {{ubl | {{cvt|64.5|mm|in|2|abbr=on}} | {{cvt|65|mm|in|2|abbr=on}} | {{cvt|74.3|mm|in|2|abbr=on}} | {{cvt|79.5|mm|in|2|abbr=on}} | {{cvt|88|mm|in|2|abbr=on}} }}
| block         = [[Cast iron]]
| head          = [[Aluminum]]
| valvetrain    = Single cam-in-head, rocker arms, 2 valves per cylinder
| compression   = {{ubl|8.5:1–9.9:1 (Naturally aspirated)|8.3:1 (Turbocharged)}}
| fuelsystem    = {{ubl|[[Weber carburetor]]|[[Manifold injection#Mechanical controlling|Mechanical fuel injection]]|[[Manifold injection#Electronic control unit|Electronic fuel injection]]|[[Manifold injection#Single-point fuel injection|Single-point injection]]|[[Manifold injection#Multi-point injection|Multi-point fuel injection]]}}
| management    = {{ubl|[[Ford EEC#EEC-IV|Ford EEC-IV]]|[[Robert Bosch GmbH|Bosch]] [[Jetronic#K-Jetronic (1973–1994)|K-Jetronic]] or [[Jetronic#KE-Jetronic (1985–1993)|KE-Jetronic]]}}[[ESC Hybrid]]
| fueltype      = [[Gasoline]]
| oilsystem     = [[Wet sump]]
| coolingsystem = [[Radiator (engine cooling)|Water-cooled]]
| turbocharger  = Some 1.6&nbsp;L versions
| power         = {{cvt|69–200|hp|kW|0|abbr=on}}
| torque        = {{cvt|86–133|lbft|Nm|0|abbr=on}}
| weight        = Circa {{cvt|100|kg|lb|0}}
}}

The '''Ford CVH engine''' is a [[Straight-four engine|straight-four]] automobile engine produced by the [[Ford Motor Company]]. The engine's name is an acronym for either ''Compound Valve-angle Hemispherical'' or ''Canted Valve Hemispherical'', where "Hemispherical" describes the shape of the combustion chamber.<ref name="efp-cvh"/><ref name="ford-enghist"/> The CVH was introduced in 1980 in the [[Ford Escort (Europe)#Third generation (1980–1986)|third generation European Escort]] and in 1981 in the [[Ford Escort (North America)#First generation (1981–1990)|first generation North American Escort]].

The CVH was produced in capacities from 1.1 to 2.0&nbsp;L, with the smallest version offered exclusively in continental Europe, and the largest only in North America. Engines for North America were built in Ford's [[Ford River Rouge Complex|Dearborn Engine]] plant, while engines for Europe and the UK were built in Ford's then-new [[Ford Bridgend Engine Plant|Bridgend Engine]] plant in [[Wales]].

==History and Details==
The engine was originally conceived in 1974, and was a key plank of the "Erika" world car programme which spawned both the third-generation European Escort and the 1981 North American car of the same name.  Although the European and North American Escorts ended up being substantially different from each other in execution, the CVH engine was the one major common part shared between them.  The CVH largely replaced the overhead valve [[Ford Kent engine|Kent ("Crossflow") engine]] in Ford of Europe's portfolio, although the 'short block' Valencia version of the Kent remained in production for many decades (ironically outliving the CVH by two years) - positioned below the CVH as an entry level engine in the smallest capacity Fiesta and Escort models.

The CVH is a cam-in-head design, a type of overhead camshaft engine with a single camshaft mounted low in the head, operating two valves per cylinder via rocker arms.<ref name="ford-enghist"/> As indicated by the name, the valves in original versions are mounted at a compound angle in order to allow for a  [[hemispherical combustion chamber]], but without the need for dual camshafts (or an elaborate rocker system) which a "hemi" engine normally requires. The later "lean burn" versions of the engine launched in 1986 had reshaped combustion chambers to improve swirl, and were strictly speaking no longer hemi-headed at all. The CVH features [[hydraulic valve lifter]]s, a first for a European Ford engine. In North America the engine was sold under different names, being called the "1.9L SEFI" from 1991 to 1996 in that market's Ford Escort, the "Split Port Induction 2000" or SPI2000 from 1997 to 2002, while from 2000 to 2004 it was simply the "Split Port" when offered in the Ford Focus.<ref name="sae-spi"/>

<gallery widths=200 heights=140>
CVH Kopf2.jpg|1.6 CVH cylinder head with valves, followers and rockers
CVH Kopf1.jpg|1.6 CVH cylinder head
CVH Kopf3.jpg|1.6 CVH cylinder head, combustion chambers
</gallery>

==1.1==
The 1.1&nbsp;L CVH had the shortest production life of the different variants. Bore × stroke are {{cvt|74| × |65|mm|in|1}}, and displacement is {{cvt|1117|cc|cuin|1}}. It debuted in the 1980 [[Ford Escort (Europe)|Escort MkIII]] for Continental Europe only, where it was offered as an alternative to the 1.1&nbsp;L [[Ford Kent engine#Valencia|Valencia]] [[Overhead valve engine|overhead valve]] (OHV) engine, which was the only 1.1&nbsp;L engine offered in UK market Escorts. The 1.1&nbsp;L CVH offered negligible improvements in economy or performance over the older Valencia unit, which was simpler and cheaper to manufacture, and hence was dropped in 1982.

Applications
* 1980–1981 [[Ford Escort (Europe)#MkIII|Ford Escort Mk 3]] (Continental Europe only)

==1.3==
The 1.3&nbsp;L CVH was introduced in the 1980 European [[Ford Escort (Europe)|Escort]] and used in the [[Ford Orion|Orion]] and [[Ford Fiesta (second generation)|Fiesta]] from 1983 to 1986. Bore and stroke are {{cvt|80x64.5|mm|in|2|abbr=on}}, for a displacement of {{cvt|1296|cc|1|abbr=on}}. The 1.3&nbsp;L was to be offered in the North American Escort, but testing found it to be unacceptably underpowered while Ford was unable to make it meet emissions requirements.<ref name=RT82>{{cite journal |editor-last=Hogg |editor-first=Tony |title=1981 Buyer's Guide |journal=Road & Track's Road Test Annual & Buyer's Guide 1981 |issue=January–February 1981 |page=97 |ref=81bg}}</ref> US production plans were scrapped just months before full-scale production was scheduled to start.

For the facelifted [[Ford Escort (Europe)#Fourth generation (1986–1992)|fourth generation European Escort]] of 1986, this CVH was replaced by a 1.3&nbsp;L Valencia engine in entry-level models, while higher trim level models used the 1.4&nbsp;L CVH described below.

Applications
* 1980–1986 [[Ford Escort (Europe)#MkIII|Ford Escort Mk 3]]
* 1983–1985 [[Ford Fiesta (second generation)|Ford Fiesta Mk 2]]
* 1983–1986 [[Ford Orion#Orion Mk I|Ford Orion Mk 1]]

==1.4==
[[File:Ford-Orion-029-scaled.jpg|thumb|1.4-litre CVH engine in an [[Ford Orion|Orion]]]]
The 1.4&nbsp;L CVH replaced the 1.3&nbsp;L CVH in the Escort, Orion and Fiesta from early 1986. Bore and stroke are {{cvt|77.2x74.3|mm|in|2|abbr=on}}, and displacement is {{cvt|1392|cc|cuin|1}}. In European trim, this engine produced {{cvt|75|hp-metric|kW|0}}.

Known as the 'Lean Burn' engine, it was designed primarily for [[Fuel economy in automobiles|fuel economy]] and featured a different cylinder head than other CVH engines.<ref name="cm-feb1986"/> The Ford variable venturi [[carburetor]] was replaced by a [[Weber carburetor|Weber]] 28/30 TLDM which used a manifold vacuum-actuated secondary choke instead of the more usual sequential linkage which opens the secondary butterfly at 3/4 to full throttle. The 1.4&nbsp;L version is less responsive to power modification than other CVH engines, and some common tuning parts cannot be used.

In South Africa, the 1.4&nbsp;L CVH was fitted to the [[Ford Laser#South Africa|Ford Laser]] and Meteor, which were rebadged [[Mazda Familia]]s. It replaced the 1.3&nbsp;L [[Mazda E engine]] used in these cars and was itself replaced by the 1.3&nbsp;L [[Mazda B engine]].

Applications
* 1986–1990 [[Ford Escort (Europe)#Mk4|Ford Escort Mk 4]]
* 1990–2000 [[Ford Escort (Europe)#MkV|Ford Escort Mk 5]]
* 1986–1989 [[Ford Fiesta (second generation)|Ford Fiesta Mk 2]]
* 1989–1995 [[Ford Fiesta (third generation)|Ford Fiesta Mk 3]]
* 1986–1990 [[Ford Orion#Orion Mk II and Mk III|Ford Orion Mk 2]]
* 1990–1992 [[Ford Orion#Orion Mk II and Mk III|Ford Orion Mk 3]]

===CVH-PTE===
The '''CVH-PTE''' is a revised version of the 1.4&nbsp;L CVH introduced on the European Ford Fiesta 1.4 Si and Ford Escort in 1994. It features [[Manifold injection#Multi-point injection|multi-point injection]] and a thicker crankcase to reduce harshness at high revs. Through the 1990s it was gradually phased out in favour of the newer [[Ford Zetec|Zetec]] 16-valve unit.

==1.6==
The [[Naturally aspirated engine|naturally aspirated]] (NA) 1.6&nbsp;L CVH debuted in the 1980 European Escort and the 1981 North American Escort. Bore and stroke are {{cvt|80x79.5|mm|in|2|abbr=on}} and total displacement is {{cvt|1597|cc|cuin|1}}.

==={{anchor|1.6EU}} European NA 1.6===
European versions produced {{cvt|79|hp-metric|kW|0|abbr=on}} with the Ford variable venturi carburetor, {{cvt|96|hp-metric|kW|0}} with the twin venturi 32/34 DFT Weber carburetor used in the Fiesta XR2 and the Escort XR3, {{cvt|105|hp-metric|kW|0}} with [[Robert Bosch GmbH|Bosch]] [[Jetronic#K-Jetronic (1973–1994)|K-Jetronic]] injection, {{cvt|90|hp-metric|kW|0}} with [[Jetronic#KE-Jetronic (1985–1993)|KE-Jetronic]] [[Manifold injection#Mechanical controlling|mechanical fuel injection]], and {{cvt|108|hp-metric|kW|0}} with [[Manifold injection#Electronic control unit|electronic fuel injection]] (EFI) and a [[Ford EEC#EEC-IV|Ford EEC-IV]] [[engine control unit]] (ECU) as found in the XR3i or Orion GLSI. A {{cvt|115|hp-metric|kW|0}} version was offered in the Escort RS1600i, developed by Ford Motorsport Germany for [[Fédération Internationale de l'Automobile|FIA]] Group A [[Homologation (motorsport)|homologation]]. This version featured a reworked cylinder head, solid cam followers and bronze bearings, and a host of other motorsport features.

European versions of the carbureted 1.6&nbsp;L engine from the 1986 model year on were revised and, like the new 1.4&nbsp;L, benefit from cylinder heads with a heart-shaped lean-burn combustion chambers and a slightly raised piston crown. The carburetor is a Weber twin venturi 28/32 TLDM unit. Power output is improved to {{cvt|90|PS|kW hp|0}} with the benefit of improved torque and fuel economy. EFI versions used in the Escort XR3i, 1.6i and Fiesta XR2i retained hemispherical combustion chambers. From the 1989 model year all EFI variants are fitted with the Ford EEC-IV ECU.

Applications
* 1980–1986 [[Ford Escort (Europe)#MkIII|Ford Escort Mk 3]]
* 1986–1990 [[Ford Escort (Europe)#Mk4|Ford Escort Mk 4]]
* 1983–1989 [[Ford Fiesta (second generation)|Ford Fiesta Mk 2]]
* 1989–1992 [[Ford Fiesta (third generation)|Ford Fiesta Mk 3]] (Replaced by [[Zetec]] from 1993 model year onward)
* 1988–1993 [[Ford Sierra]]
* 1983–1986 [[Ford Orion#Orion Mk I|Ford Orion Mk 1]]
* 1986–1990 [[Ford Orion#Orion Mk II and Mk III|Ford Orion Mk 2]]
* 1990–1992 [[Ford Orion#Orion Mk II and Mk III|Ford Orion Mk 3]]
* 1990–1991 [[Ford Escort (Europe)#MkV|Ford Escort Mk 5]] (Replaced by [[Zetec]] in 1992)
* 1989–1992 [[Ginetta G32]]
* 1982–1991 [[Morgan 4/4#4/4 1600|Morgan 4/4 1600]]

===Chinese NA 1.6===
[[Chery]] manufactured a 1.6&nbsp;L CVH for use in their [[SEAT Toledo#First generation (Typ_1L; 1991)|SEAT Toledo]] based vehicles.<ref>{{Cite web |date=2021-05-15 |title=The Seat cars made in China | work = ChinaCarHistory |url=https://chinacarhistory.com/2021/05/15/the-seat-cars-made-in-china/ |access-date=2022-12-10 | first = Erik | last = Van Ingen Schenau }}</ref> Chery purchased the production line for this engine in England, which was then transferred to Anhui. The first engines left the production line in May 1999.<ref name="Hessler65">{{citation | title = Country Driving | last = Hessler | first = Peter | publisher = HarperCollins | location = New York, NY | date = 2010 | isbn = 978-0-06-180409-0 | page = 65 | url-access = registration | url = https://archive.org/details/countrydrivingjo00hess_0/page/64 }}</ref> The engine is codenamed '''SQR480.''' Chery replaced the CVH with their own [[Chery ACTECO engine|ACTECO engines]].

Applications:
* 1999–2006 [[Chery A11]]

===North American NA 1.6===
Standard 1.6&nbsp;L output started at {{cvt|65|hp|kW|0}} and {{cvt|85|lbft|Nm|0|abbr=on}}. The early North American engines are built with cast pistons and connecting rods, a low-flow version of the CVH head, flat hydraulic lifters, a 0.229" lift camshaft, 32/32 Weber-licensed carburetor, cast exhaust manifold, and low-dome pistons. Over the years compression ratios ranged from 8.5:1–9.0:1, while power started at {{cvt|65|hp|kW|0}} in 1981, rising to {{cvt|74|hp|kW|0}} by 1985.

A 1.6&nbsp;L High Output (HO) motor became available in late 1982 through 1985. Changes to it included a 4-2-1 header, higher-lift (0.240") camshaft, a 32/34 Weber carburetor, a dual-snorkel air-box, and high-dome pistons making 9.0:1–9.5:1 compression making {{cvt|74|hp|kW|1}} in 1982 and {{cvt|80|hp|kW|1}} in 1983–1985.

A 1.6&nbsp;L EFI motor became an option in 1983 through 1985. It had all the features of the HO (Higher Output) motor but had a totally different intake system to allow for multi-point EFI running on Ford's EEC-IV ECU. The 1.6 EFI shares the same head as the carbureted 1.6 found in North America but without a mechanical fuel pump. The 1.6 EFI engine was replaced by the 1.6 HO in all high-altitude regions, making the 1.6 EFI a rare model.

Applications
* 1981–1984 [[Ford Escort (North America)#First generation (1981–1990)|Ford Escort]]
* 1981–1984 [[Mercury Lynx]]
* 1982–1983 [[Mercury LN7]]
* 1982–1985 [[Ford EXP]]

==1.6 Turbo==

===European Turbo 1.6===
A turbocharged version of the 1.6&nbsp;L was developed by Ford Europe for the RS Turbo Escort and the later [[Ford Fiesta RS Turbo]]. It makes {{cvt|132|hp-metric|kW|0}} at 6,000&nbsp;rpm, and {{cvt|133|lbft|Nm|0|abbr=on}} of torque at 3,000&nbsp;rpm. The block is modified to provide an oil return from the [[turbocharger]]. [[Crankshaft]] and [[connecting rod]]s are identical to the standard 1.6&nbsp;L models, but the [[Mahle GmbH|Mahle]] pistons are unique to the RS Turbo, and are manufactured using a pressure cast method which makes them considerably stronger and more expensive than the normal cast pistons. The compression ratio was reduced to 8.3:1, allowing the use of higher boost pressure. The engine only needs {{cvt|7|psi|bar|abbr=on}} of boost to produce its quoted power output.

Applications
* 1980–1986 [[Ford Escort (Europe)#MkIII|Ford Escort Mk 3]]
* 1986–1990 [[Ford Escort (Europe)#Mk4|Ford Escort Mk 4]]
* 1989–1995 [[Ford Fiesta (third generation)|Ford Fiesta Mk 3]]

===North American Turbo 1.6===
The North American 1.6 turbocharged CVH was developed by Ford's Special Vehicle Operations (SVO) with help from Jack Roush for 1984 and 1985 in the Ford EXP Turbo, Ford Escort GT Turbo, and Mercury Lynx RS Turbo. At {{cvt|120|hp|0|abbr=on}}, its output is 50% higher than the carbureted North American 1.6&nbsp;L HO, making it the most powerful production CVH offered in North America while returning impressive fuel efficiency and without reducing the engine's lifespan. The turbocharged engine featured a specially designed cam profile (0.240", comparable to the 1.6 HO and EFI camshafts), a Ford Performance/SVO modified head (comparable to European 1.6s), the EFI intake manifold, a unique cast exhaust manifold, low-dome pistons, and Ford's top-of-the-line EFI and ECU. These engines only appeared in the 1984–1985 Ford Escort GT Turbo and 1984–1985 Ford EXP Turbo, of which only about 10,000 were made in total. The 1.6 turbocharged Fords came standard with a TRX package that included upgraded suspension and specialty Michelin tires.

Applications
* 1984–1985 [[Ford Escort (North America)#First generation (1981–1990)|Ford Escort]]
* 1984–1985 [[Mercury Lynx]]
* 1984–1985 [[Ford EXP]]

==1.8==
The 1.8&nbsp;L CVH was only used in the European Ford Sierra. Bore is the same {{cvt|80|mm|2|abbr=on}} as the 1.6&nbsp;L CVH, but a different crankshaft with a stroke of {{cvt|88|mm|2|abbr=on}} raises displacement to {{cvt|1769|cc|1|abbr=on}}. The cylinder head is equipped with hydraulic roller camshaft followers to reduce noise.
Utilises an ESC Hybrid management system, and a Pierburg 2E3 carburettor or single point fuel injection on later models.

Applications
* 1989–1993 [[Ford Sierra]] (Replaced the [[Ford Pinto engine]] from 1989 model year onward)

{{clear}}

==1.9==
[[File:1990 Ford Escort GT, 1.9 HO engine (Hershey 2019).jpg|thumb|1.9&nbsp;L "High Output" EFI engine in a 1990 Ford Escort GT]]
The CVH was enlarged to 1.9&nbsp;L for the 1986 model year North American Escort. Bore and stroke are {{cvt|82x88|mm|in|2|abbr=on}}. This stroke length was later used in the 2.0&nbsp;L CVH engine, and again in the ''[[Ford Zeta engine|Zeta]]'' engine which replaced it. The long stroke necessitated a raised engine block deck, a design also shared with later units. All 1.9s from 1989 on are equipped with a roller camshaft and roller lifters. The camshaft and water pump are driven by the timing belt. This engine is a [[Non-interference engine|non-interference]] design. Output is {{cvt|86|hp|kW|0|abbr=on}} and {{cvt|100|lbft|Nm|0|abbr=on}} with a carburetor. In models with electronic [[Manifold injection#Single-point injection|single-point fuel injection]] (or throttle-body injection, called Central Fuel Injection (CFI) by Ford), an additional {{cvt|4|hp|kW|abbr=on}} is produced, while torque is little changed.

Multi-point fuel injection and hemispherical combustion chambers are features of the 1986 Escort GT's EFI HO engine, raising output to {{cvt|108|hp|kW|0|abbr=on}} and {{cvt|114|lbft|Nm|0|abbr=on}}.

The {{cvt|90|hp|kW|0|abbr=on}} 1.9&nbsp;L CFI engine of the late 1980s, particularly when equipped with either the four- or five-speed manual [[transaxle]], was noted for delivering outstanding fuel economy. The four-speed Escort Pony models achieved better mileage than five-speed cars, with upwards of {{cvt|30|mpgus|abbr=on}} in city driving and {{cvt|40–45|mpgus|abbr=on}} on the highway not being uncommon.

The second generation American Escort received [[Manifold injection#Sequential injection|sequential electronic fuel injection]] (SEFI) for 1991–1996 (sharing the same head as the 1.9 CFI), but power and torque are little changed at {{cvt|88|hp|kW|0|abbr=on}} and {{cvt|108|lbft|Nm|0|abbr=on}} respectively.

Applications
* 1986–1996 [[Ford Escort (North America)#First generation (1981–1990)|Ford Escort]]
* 1985–1987 [[Mercury Lynx]]
* 1991–1996 [[Mercury Tracer#Second generation (1991–1996)|Mercury Tracer]]
* 1986–1988 [[Ford EXP]]
* Gen 2 [[Spec Racer Ford]]

==2.0==
The 2.0&nbsp;L was introduced in the 1997 North American [[Ford Escort (North America)#1997|Escort]] sedan and wagon as the SPI2000. Ford's Split Port Induction (SPI) system is a form of [[variable-length intake manifold]]. In this system, the intake path to each intake valve is split into primary and secondary passages. The primary passage contains the injector for the cylinder, and introduces the air tangentially to the cylinder for maximum swirl. The secondary passage contains an intake manifold runner control (IMRC) deactivation valve which opens for high speed and wide-open throttle (WOT) situations to provide a minimally restricted path for additional air to maximize volumetric efficiency and power.<ref name="sae-spi"/> With SPI this engine produces {{cvt|110|hp|kW|0}} and {{cvt|125|lbft|Nm|0}}. The additional displacement is achieved by boring the 1.9&nbsp;L engine to {{cvt|84.8|mm|in|2}}. As with the 1.9, the water pump is driven by the timing belt. Like the 1.9&nbsp;L, this engine is a non-interference design. It is the last CVH engine made, and production ended with the 2004 Ford Focus LX/SE sedan and wagons. These engines have "2.0L Split Port" in raised letters on the top of the valve cover.

Applications
* 1997–2002 [[Ford Escort (North America)#Third generation (1997–2003)|Ford Escort]]
* 1997–1999 [[Mercury Tracer#Third generation (1997–1999)|Mercury Tracer]]
* 2000–2004 [[Ford Focus (first generation)#North America|Ford Focus Mk1 (North America)]]

==Common problems==
===Noise, vibration, harshness===
Throughout its 20-year production life, the CVH had a reputation for excessive [[noise, vibration, and harshness]] (NVH). [[Jeremy Clarkson]] said of the CVH-powered Escort that "''it was powered by engines so rough, even [[Moulinex]] wouldn't use them''".<ref name="gomog-hist"/> This harshness is mostly due to the cylinder head and valvetrain design.{{citation needed|date=December 2024}} At {{cvt|220|lb|abbr=on}} at full lift, the valve springs in the CVH are considerably stiffer than is typical in other engines. The stiff springs are needed to overcome the weight of the rocker arms and hydraulic self-adjusting tappets used and thereby prevent valve float, which they do up to around 6700 rpm. The stiff valve springs add more friction and pressure to the already high-friction "flat tappet" design.

===Sludge===
The camshaft is oiled by small holes in the cylinder head casting next to the lifter bores. These holes are prone to blocking up with [[oil sludge]] if the engine is not serviced regularly, starving the camshaft of oil. The CVH is known for producing excessive sludge if the service schedule is ignored or if poor quality oil is used. The cause is the design of the crankcase ventilation circuit, which Ford revised several times over the engine's lifetime but never completely cured. Due to this, camshaft and tappet wear problems are common. A worn camshaft can cause heavy clattering and ticking from the engine's top end, especially at high engine speeds.<ref name="gomog-hist"/>

===Valve seat failure===
A common problem with later CVHs is their tendency to drop a valve seat,<ref name="Valve seat problems"/> which happens most often in VIN number P engines. This can occur with no warning, even if the engine has been well maintained. In most cases, a seat drops on the number 4 cylinder, with the next most common being the number 2 cylinder. With the factory valve seats, the typical life of the 2.0&nbsp;L SPI in a Focus is about {{cvt|100000|to|120000|mi|km|abbr=on}},<ref name="Valve seat life"/> but a failure can happen as early as {{cvt|70000|mi|km|abbr=on}}. When the valve seat drops out of the cylinder head, it falls into the cylinder and damages the cylinder wall, [[piston]], and [[cylinder head]]. In some cases, the valve seat is drawn from its cylinder through the [[intake manifold]] into another cylinder, where it causes damage.

==Kits cars, limited production cars, tuners==
Apart from Ford's own models, the CVH engine was used in a number of vehicles built by small volume manufacturers, and was offered as an option in some owner-assembled cars. Several companies also began supplying performance parts and complete engines for CVH owners in search of more power.

Small volume applications:
* 1984–1990 [[Reliant Scimitar SS1]] — 1.3&nbsp;L, 1.4&nbsp;L, 1.6&nbsp;L<ref name="av-scimitar"/>
* 1990–1992 [[Reliant Scimitar SS1|Reliant Scimitar SST]] — 1.3&nbsp;L, 1.4&nbsp;L<ref name="ae-sst"/>
* 1992–1993 [[Reliant Scimitar SS1|Reliant Scimitar Sabre]] — 1.4&nbsp;L
* 1982–1993 [[Morgan 4/4#Ford CVH engine|Morgan 4/4]] — 1.6&nbsp;L<ref name="hillbook"/>
* 1983–1989 [[Panther Kallista]] — 1.6&nbsp;L<ref name="msm-jul1989"/>

Kit car applications:
* [[Westfield Sportscars]] SE — 1.6&nbsp;L
* [[Sylva Autokits#Mojo|Sylva Mojo]] and Mojo 2
* Stuart Taylor Mark 1.<ref name="makk-stuarttaylor"/>

Tuners:
* Burton Power.<ref name="bp-cvh"/>
* Specialised Engines.<ref name="se-cvh"/>
* Ferriday Engineering.<ref name="fe-cvh"/>
* Norris Motorsport.<ref name="nms-cvh"/>

==Hybrid engines==
=== Schrick 16V ===
In 1982 the German company ''Dr. Schrick GmbH'', later renamed ''AVL Schrick'', developed a [[Overhead camshaft engine#Double overhead camshaft (DOHC)|double overhead camshaft]] (DOHC) [[multi-valve]] cylinder head for the 1.6&nbsp;L CVH block.<ref name="ff-jan2014"/><ref name="cf-jul2020"/> Each of the two overhead camshafts is installed in a separate camshaft carrier that is attached to the main body of the cylinder head. Each carrier has its own cam cover. Fitted with an original RS1600i engine intake manifold, a tubular exhaust manifold, and modified ignition, prototype engines developed {{cvt|99|kW|hp|0}}.

In contrast to cylinder head conversions produced for Ford by [[Cosworth]], the Schrick cylinder head never went into series production. With the introduction of the multi-valve Zetec engine, Schrick stopped development.

=== ZVH/ZE-VH ===
The ZVH or ZE-VH engine mounts a CVH 8 valve cylinder head on a Zeta/Zetec engine block.<ref name="jh-zvh"/> This is possible because the cylinder bore spacing, locations of the water and oil passages, and the cylinder head bolts on these engines are identical. 

This combination of parts allowed the owner of a CVH-powered car to retain the cylinder head and associated parts from the original engine while substituting a stronger, large displacement engine block. Some builders have built ZVH engines that used the cylinder head, fuel injection system, ignition system, exhaust manifold, and turbocharger from the Escort RS combined with a Zetec block.

The engine's name indicates a '''Z'''etec/C'''VH''' hybrid.

==See also==
* [[Ford CHT engine]]
* [[List of Ford engines]]

==References==
{{Reflist|refs=

<ref name="efp-cvh">{{cite web |url=https://www.escortfocus.com/html/cvh.html |title=The CVH Engines |author=<!--Not stated--> |date= |website=Escort-Focus Performance |publisher= |access-date= }}</ref>

<ref name="ford-enghist">{{cite web |url=https://performanceparts.ford.com/download/pdfs/EngineHistory.pdf |title=Engine History — Four-Cylinder Engine Section |author=<!--Not stated--> |date= |website=performanceparts.ford.com |publisher=Ford Racing |access-date= }}</ref>

<ref name="sae-spi">{{cite journal |last1=Stockhausen |first1=William F. |last2=Wiemero |first2=Timo A. |last3=Ives |first3=David C. |last4=Kronik |first4=Anatoly Y. |date=1 May 1996 |title=Development and Application of the Ford Split Port Induction Concept |url=https://www.sae.org/publications/technical-papers/content/961151/ |journal=SAE Transactions |volume=105 |issue= |pages=1494–1507 |doi= |access-date= |issn=0148-7191 |jstor=44736376 }}</ref>

<ref name="cm-feb1986">{{cite magazine |author=<!--Staff writer(s); no by-line.--> |date=1 February 1986 |title=Lean burn for Escort |url=https://archive.commercialmotor.com/article/1st-february-1986/14/lean-burn-for-escort |magazine=Commercial Motor |page=14 |location= |publisher= |access-date=}}</ref>

<ref name="gomog-hist">{{cite web |url=https://www.gomog.com/allmorgan/cvhhistory.html |title=Ford CVH Engine History |last=Goldman |first=Lorne |date= |website=www.gomog.com |publisher= |access-date= }}</ref>

<ref name="Valve seat problems">{{cite web |url=http://mechdb.com/index.php/Valve_seat |title=2.0L SPI valve seat problems |accessdate=2011-05-29 |url-status=dead |archiveurl=https://web.archive.org/web/20110410232239/http://mechdb.com/index.php/Valve_seat |archivedate=2011-04-10}}</ref>

<ref name="Valve seat life">{{cite web |url=http://www.focusfanatics.com/forum/showthread.php?t=254262 |title=Valve seat life |accessdate=2011-05-29}}</ref>

<ref name="av-scimitar">{{cite web |url=http://www.autovehicle.info/reliant-scimitar-ss1/detay/reliant-scimitar-ss1---sst-1984-1992-7733.html |title=Reliant Scimitar SS1 / SST (1984 - 1992) |author=<!--Not stated--> |date= |website=Autovehicle.info |publisher= |access-date= }}</ref>

<ref name="ae-sst">{{cite web |url=https://www.autoexpress.co.uk/car-reviews/93807/reliant-scimitar-sst |title=Reliant Scimitar SST |author=<!--Not stated--> |date=16 December 2015 |website=Auto Express |publisher= |access-date= }}</ref>

<ref name="hillbook">{{cite book |last=Hill |first=Ken |author-link= |date=15 October 2019 |title=Completely Morgan: Four-Wheelers 1968 to 1994 |url= |location= |publisher=Veloce Publishing |page= |isbn=978-1787112629 }}</ref>

<ref name="msm-jul1989">{{cite magazine |last=Kimberley |first=William |date=July 1989 |title=Panther Kallista |url=https://www.motorsportmagazine.com/archive/article/july-1989/57/panther-kallista |magazine=Motor Sport |location= |publisher= |access-date=}}</ref>

<ref name="makk-stuarttaylor">{{cite web |url=https://www.madabout-kitcars.com/kitcar/kitcar_details.php?80 |title=Mark 1 from Stuart Taylor |author=<!--Not stated--> |date= |website=www.madabout-kitcars.com |publisher= |access-date= }}</ref>

<ref name="bp-cvh">{{cite web |url=https://www.burtonpower.com/tuning-guides/tuning-guide-pages/ford-cvh-tuning-guide.html |title=Ford CVH Tuning Guide |author=<!--Not stated--> |date= |website=Burton Power |publisher= |access-date= }}</ref>

<ref name="se-cvh">{{cite web |url=http://www.specialisedengines.co.uk/cvh/dir11.html |title=C.V.H. |author=<!--Not stated--> |date= |website=Specialised Engines |publisher= |access-date= }}</ref>

<ref name="fe-cvh">{{cite web |url=http://www.ferriday.co.uk/cvh/ |title=Performance CVH |author=<!--Not stated--> |date= |website=Ferriday Engineering |publisher= |access-date= }}</ref>

<ref name="nms-cvh">{{cite web |url=https://www.norrismotorsport.co.uk/performance-tuning/vehicle-engine/ford-rs-turbo/ |title=Ford CVH Escort/Fiesta RS Turbo |author=<!--Not stated--> |date= |website=Norris Motorsport |publisher= |access-date= }}</ref>

<ref name="ff-jan2014">{{cite magazine |last=Brannan |first=Ade |date=30 January 2014 |title=Mk3 Escort |url=https://www.pressreader.com/australia/fast-ford/20140130/281543698861613 |magazine=fast ford |location= |publisher= |access-date=}}</ref>

<ref name="cf-jul2020">{{cite web |url=https://www.classicfordmag.co.uk/features/head-case-the-herbst-escort/ |title=Head Case: The Herbst Escort |last=Brannan |first=Adrian |date=11 July 2020 |website=Classic Ford |publisher= |access-date= }}</ref>

<ref name="jh-zvh">{{cite web |url=http://www.quantums.info/zvh.htm |title=Zetec/CVH hybrid engine for the Quantum |last=Hearne |first=Jim |date=24 December 2018 |website=www.quantums.info |publisher= |access-date= }}</ref>

}}

==Further reading==
* {{cite book |last=Wallage |first=Peter |author-link= |date=15 July 2000 |title=Rebuilding and Tuning Ford's CVH Engine |url= |location= |publisher=Haynes Publishing |page= |isbn=978-1859600061 }}

==External links==
{{Commons category|Ford CVH engine}}
* {{cite web |url=https://classicsworld.co.uk/guides/ford-cvh-engine-everything-you-need-to-know/ |title=Ford CVH Engine: Everything You Need To Know |last=Bell |first=Matt |date=5 February 2021 |website=Classics World |publisher= |access-date= }}
* {{cite web |url=https://www.gomog.com/allmorgan/cvh.html |title=Ford CVH Tuning Guide |last=Baker |first=David |date= |website=www.gomog.com |publisher= |access-date= }}

{{Ford engine timeline}}

{{DEFAULTSORT:Ford CVH Engine}}

[[Category:Ford engines|CVH]]
[[Category:Gasoline engines by model]]
[[Category:Straight-four engines]]