The Circle L is an
automobile
A car or automobile is a motor vehicle with wheels. Most definitions of ''cars'' say that they run primarily on roads, seat one to eight people, have four wheels, and mainly transport people instead of goods.
The year 1886 is regarded ...
engine produced by
GM Powertrain Poland in
Poland
Poland, officially the Republic of Poland, , is a country in Central Europe. Poland is divided into Voivodeships of Poland, sixteen voivodeships and is the fifth most populous member state of the European Union (EU), with over 38 mill ...
. It is a
inline-four
A straight-four engine (also called an inline-four) is a four-cylinder piston engine where cylinders are arranged in a line along a common crankshaft.
The vast majority of automotive four-cylinder engines use a straight-four layout (with the e ...
16-valve
In automotive engineering a multi-valve or multivalve engine is one where each cylinder has more than two valves. A multi-valve engine has better breathing and may be able to operate at higher revolutions per minute (RPM) than a two-valve engine, ...
turbocharged
In an internal combustion engine, a turbocharger (often called a turbo) is a forced induction device that is powered by the flow of exhaust gases. It uses this energy to compress the intake gas, forcing more air into the engine in order to pro ...
diesel engine
The diesel engine, named after Rudolf Diesel, is an internal combustion engine in which ignition of the fuel is caused by the elevated temperature of the air in the cylinder due to mechanical compression; thus, the diesel engine is a so-ca ...
originally designed by
Isuzu but now owned by
General Motors. The engine is produced in
Europe
Europe is a large peninsula conventionally considered a continent in its own right because of its great physical size and the weight of its history and traditions. Europe is also considered a subcontinent of Eurasia and it is located enti ...
by
General Motors for use in the
Opel
Opel Automobile GmbH (), usually shortened to Opel, is a German automobile manufacturer which has been a subsidiary of Stellantis since 16 January 2021. It was owned by the American automaker General Motors from 1929 until 2017 and the PSA ...
,
Vauxhall
Vauxhall ( ) is a district in South West London, part of the London Borough of Lambeth, England. Vauxhall was part of Surrey until 1889 when the County of London was created. Named after a medieval manor, "Fox Hall", it became well known for ...
and
Chevrolet vehicles and by
Honda
is a Japanese public multinational conglomerate manufacturer of automobiles, motorcycles, and power equipment, headquartered in Minato, Tokyo, Japan.
Honda has been the world's largest motorcycle manufacturer since 1959, reaching a producti ...
for use in the
Civic compact car
Compact car is a vehicle size class — predominantly used in North America — that sits between subcompact cars and mid-size cars. "Small family car" is a British term and a part of the C-segment in the European car classification. However ...
.
History
In the late nineties the Japanese company
Isuzu, which was known for the efficiency of its diesel engines, collaborated with
General Motors on a new diesel engine for the European market for
Opel
Opel Automobile GmbH (), usually shortened to Opel, is a German automobile manufacturer which has been a subsidiary of Stellantis since 16 January 2021. It was owned by the American automaker General Motors from 1929 until 2017 and the PSA ...
and
Vauxhall
Vauxhall ( ) is a district in South West London, part of the London Borough of Lambeth, England. Vauxhall was part of Surrey until 1889 when the County of London was created. Named after a medieval manor, "Fox Hall", it became well known for ...
. For this purpose it opened a new plant in the city of
Tychy
Tychy (Polish pronunciation: ; german: Tichau; szl, Tychy) is a city in Silesia in southern Poland, approximately south of Katowice. Situated on the southern edge of the Upper Silesian industrial district, the city boders Katowice to the north, ...
, in Poland, called Isuzu Motor Polska.
Characteristics
For reasons of economy, GM and Isuzu chose not to make an engine from scratch, but rather evolved the new engine from an existing base. Thus, the
Isuzu 4EE1 1.7-liter was chosen and developed into the "Circle L" family of engines, also known as the 4EE2.
The engine kept the same dimensions of 1.7 4EE1. The main differences are in the DOHC
camshaft
A camshaft is a shaft that contains a row of pointed cams, in order to convert rotational motion to reciprocating motion. Camshafts are used in piston engines (to operate the intake and exhaust valves), mechanically controlled ignition systems ...
s and
direct injection. The first engines mounted a simple direct injection and met the
Euro 3
The European emission standards are vehicle emission standards for pollution from the use of new land surface vehicles sold in the European Union and EEA member states and the UK, and ships in EU waters. The standards are defined in a ser ...
standard, while the later engines met
Euro 4
The European emission standards are vehicle emission standards for pollution from the use of new land surface vehicles sold in the European Union and EEA member states and the UK, and ships in EU waters. The standards are defined in a ser ...
and used
common rail
Common rail direct fuel injection is a direct fuel injection system built around a high-pressure (over ) fuel rail feeding solenoid valves, as opposed to a low-pressure fuel pump feeding unit injectors (or pump nozzles). High-pressure injectio ...
injection technology. The 1.7 Circle L common rail engines were the first common rail engines used in Opels.
60 percent of the components for the production of the engines at Isuzu Motor Polska come from Germany, as well as the
aluminium alloy
An aluminium alloy (or aluminum alloy; see spelling differences) is an alloy in which aluminium (Al) is the predominant metal. The typical alloying elements are copper, magnesium, manganese, silicon, tin, nickel and zinc. There are two princip ...
for the manufacture of the cylinder head. The Polish plant was responsible for the construction and the development of the valvetrain. The block, however, comes to Tychy already built by the Isuzu factory in Hokkaido, Japan.
These engines are particularly important for Opel since they are fitted to their best-selling models in a period in which diesel engines became extremely popular. Moreover, thanks to their great
fuel economy and reduced emissions, Circle L engines were integrated into the family of Ecotec engines. Later Circle L engines became part of the Ecoflex family.
The 1.7-liter 4EE2 was offered in six variants, whose characteristics and applications are described below.
Y17DT
The abbreviation Y17DT identifies the very first Circle L engine: As already mentioned it is a Euro 3 engine with a compression ratio of 18.4:1. The unit has
Denso engine management, as in most Circle L engines. A Mitsubishi TD025 turbocharger is fitted, as is an
exhaust gas recirculation
In internal combustion engines, exhaust gas recirculation (EGR) is a nitrogen oxide () emissions reduction technique used in petrol/gasoline, diesel engines and some hydrogen engines. EGR works by recirculating a portion of an engine's exhaust ...
system. The Y17DT reaches at 4400 rpm, with a torque of between 1800 and 3000 rpm. This engine was fitted in:
*Opel Corsa C 1.7 DTI 16V 75 HP (2000-03);
*Opel Combo C 1.7 DTI 16V (2002-04);
*Opel Astra G 1.7 DTI 16V (1999-2003);
*Opel Meriva 1.7 16V DTI (2003-05);
Y17DTL
The engine Y17DTL is a reduced power variant of the Y17DT, to which it differs in the absence of an intercooler. Maximum power is reduced to at 4400 rpm, and maximum torque to between 2000 and 3000 rpm. This engine, also Euro 3, was fitted in:
*Opel Corsa C 1.7 16V 65 HP (2000-03);
*Opel Combo C 1.7 DI 16V (2002-04);
Z17DTL
The engine Z17DTL was one of the first common rail
turbo-diesel engine
The term turbo-diesel, also written as turbodiesel and turbo diesel, refers to any diesel engine equipped with a turbocharger. As with other engine types, turbocharging a diesel engine can significantly increase its efficiency and power output, ...
s used by Opel. With a turbocharger and a compression ratio of 18.4:1, it can reach the maximum power of at 4400 rpm, with a maximum torque of at 1800 rpm. It was fitted in:
* Opel Astra G 1.7 16V CDTI (2003-04)
* Opel Astra H 1.7 CDTI (2004- 05)
Z17DT
The engine Z17DT was one of the first common rail turbo diesel engines used by Opel. With a
variable-geometry turbocharger
Variable-geometry turbochargers (VGTs), occasionally known as variable-nozzle turbines (VNTs), are a type of turbochargers, usually designed to allow the effective aspect ratio of the turbocharger to be altered as conditions change. This is done ...
and a compression ratio of 18.4:1, can reach the maximum power of at 4400 rpm, with a maximum torque of at 2300 rpm. It was fitted in:
*Opel Corsa C 1.7 16V CDTI 101CV (2003-06);
*Opel Meriva A 1.7 CDTi 16v 101CV (2003-05);
This engine meets the Euro 4 directive.
Z17DTH and A17DT
This motor is similar to the one signed Z17DT it replaces, and features a number of minor improvements. The power is unchanged at at 4400 rpm, but the torque increases to at 2300 rpm. It was fitted in
*Opel Meriva A 1.7 CDTI A (2005-10),
*Opel Astra H 1.7 CDTI (2004-08),
*Opel Combo C 1.7 CDTI (2004-2010).
*Opel Corsa C 1.7 CDTI (2003-06)
With the exception of the Opel Astra 1.7 CDTI 16V, this car had a
Bosch
Bosch may refer to:
People
* Bosch (surname)
* Hieronymus Bosch (c. 1450 – 1516), painter
* Van den Bosch, a Dutch toponymic surname
* Carl Bosch, a German chemical engineer and nephew of Robert Bosch
* Robert Bosch, founder of Robert Bosch Gm ...
engine management system
An engine control unit (ECU), also commonly called an engine control module (ECM), is a type of electronic control unit that controls a series of actuators on an internal combustion engine to ensure optimal engine performance. It does this by re ...
, and the other four models are equipped with a Denso control unit. In more modern versions, introduced in 2010, this engine delivers of maximum power at 4000 rpm, while maximum torque is always , but delivered between 1,700 and 2,550 rpm. In this configuration, this engine has been fitted to:
*Opel Meriva B 1.7 CDTI (2010-13)
Z17DTR and A17DTR
These are more powerful variants (but not the most powerful) of the Circle L engines. They also meet the Euro 4 standard, but feature a slightly lower compression ratio of 18.2:1. As in all Euro 4 engine an exhaust gas recirculation system is present. The maximum power reaches at 4000 rpm, with a peak torque of between 2000 and 2700 rpm.
This engine was fitted in:
*Opel Corsa D 1.7 CDTI 16V 125hp (2006-11);
*Opel Corsa D GSi 1.7 CDTI ( 2007 -11);
*Opel Meriva 1.7 CDTI 16V 125hp (2006-10);
*Opel Astra 1.7 16V 5p CDTI 125hp (2007-09);
*Opel Astra H SW 1.7 CDTI 16V 125hp (2007-10);
*Opel Astra GTC 1.7 CDTI 16V 125hp (2007- 11 ).
The abbreviation A17DTR identifies the
Euro 5 variant, which has otherwise identical features and is fitted in:
*Opel Zafira B 1.7 CDTI 16V 125hp ( 2009 -14);
*Opel Astra J 1.7 CDTI 125hp (2010-11).
A17DTS
In 2010 the engine A17DTR was developed into the A17DTS: here the engine power has been increased to at 4000 rpm, while the maximum torque is increased to between 2000 and 2500 rpm. This variant has been fitted in:
*Opel Corsa D 1.7 CDTI (2011-13);
*Opel Astra J 1.7 CDTI 130cv (2011-14);
*Opel Meriva B 1.7 CDTI 130cv (2010-13);
*Opel Mokka 1.7 CDTI ( 2012 -15);
*Chevrolet Cruze 1.7 VCDi (2012-14);
*Chevrolet Trax 1.7 D ( 2013 - 15 ).
Z17DTJ and A17DTJ
This engine was the basis for the 1.7 Ecoflex: Maximum power reaches at 3800 rpm, with a maximum torque of at 2000 rpm.
It is fitted in:
*Opel Astra H 1.7 CDTI 16v 110 bhp (2007-09);
*Opel Astra J 1.7 CDTI 16v 110 bhp (2010-15);
*Opel Astra GTC H / SW 1.7 CDTI 16v 110 bhp (2007-10 );
*Opel Zafira B 1.7 CDTi 16v 110HP (2007-08).
A17DTC and A17DTE
This is the second diesel engine in the Opel engine range to be included in the EcoFlex range (the first was a 1.3 Multijet engine from Fiat). Introduced in 2008, is based on the Z17DTJ engine developed simultaneously, and is characterized by a reduction of friction of the moving parts in order to optimize the thermal efficiency and meet the stricter Euro 5 standard. Outputs are identical to those of the Z17DTJ. It is fitted in:
*Opel Meriva B 1.7 CDTi 16v 110HP (from 2010);
*Opel Zafira B 1.7 CDTi 16v 110HP (2008-14);
*Opel Astra J 1.7 CDTI 16v 110HP (2010-14).
Honda
The Honda version features
common rail
Common rail direct fuel injection is a direct fuel injection system built around a high-pressure (over ) fuel rail feeding solenoid valves, as opposed to a low-pressure fuel pump feeding unit injectors (or pump nozzles). High-pressure injectio ...
direct injection technology, while the Opel ''4EE2'' unit uses low-pressure DI. Honda's purchase of the Circle-L engines was reciprocated by GM's purchase of the ''
J35A3''
V6.
Applications:
*
Honda Civic
The is a series of automobiles manufactured by Honda since 1972. Since 2000, the Civic has been categorized as a compact car, while previously it occupied the subcompact class. , the Civic is positioned between the Honda Fit/City and Hond ...
(Europe)
4EE2
The 4EE2 produces at 4400 rpm and at 1800 rpm.
Applications:
*
Opel Corsa
The Opel Corsa is a supermini car engineered and produced by the German automobile manufacturer Opel since 1982. Throughout its existence, it has been sold under a variety of other brands owned by General Motors (most notably Vauxhall, Chev ...
*
Opel Meriva
The Opel Meriva is a car manufactured and marketed by the German automaker Opel on its Corsa platform, from May 2003 until June 2017 across two generations. Described as a mini MPV, it was marketed as the Vauxhall Meriva in the United Kingdom, ...
*
Opel Astra
The Opel Astra is a compact car/ small family car ( C-segment) developed and produced by the German automaker Opel since 1991, currently at its sixth generation. It was first launched in September 1991 as a direct replacement to the Opel Kad ...
*
Opel Zafira
The Opel Zafira is a car manufactured and marketed across three generations between 1999 and 2019 by Opel. Based on the Opel Astra platform, it is developed to occupy the multi-purpose vehicle (MPV) segment.
The Zafira was also marketed unde ...
*
Opel Vectra
The Opel Vectra is a mid-size car ( large family car) that was engineered and produced by the German automaker Opel from 1988 until 2010. Available in saloon, hatchback and estate body styles, the Vectra was also sold by the Vauxhall marq ...
* Cummins MerCruiser Recreational Sterndrive, Inboard or Jet (Boat Engine)
See also
*
List of GM engines
This list of GM engines encompasses all engines manufactured by General Motors and used in their cars.
Divisions
When General Motors was created in 1908, it started out with Buick and soon after acquired Oldsmobile, Cadillac and Oakland. There w ...
*
DMAX
*
Honda N series diesel engine
External links
Isuzu Builds 1,000,000th Circle-LMercruiser BrochureMercruiser BrochureMercruiser Brochure
{{Honda automotive engine timeline (2000-present)
Circle L
Honda engines
Diesel engines by model
Straight-four engines