Northstar Engine Series
   HOME

TheInfoList



OR:

The Northstar engine is a family of high-performance 90°
V engine A V engine, sometimes called a Vee engine, is a common configuration for internal combustion engines. It consists of two cylinder banks—usually with the same number of cylinders in each bank—connected to a common crankshaft. These cylinder ...
s produced by
General Motors The General Motors Company (GM) is an American Multinational corporation, multinational Automotive industry, automotive manufacturing company headquartered in Detroit, Michigan, United States. It is the largest automaker in the United States and ...
between 1993 and 2011. Regarded as GM's most technically complex engine, the original
double overhead cam An overhead camshaft (OHC) engine is a piston engine where 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 combustion cha ...
, four valve per cylinder, aluminum block/aluminum head V8 design was developed by Oldsmobile R&D, but is most associated with
Cadillac The Cadillac Motor Car Division () is a division of the American automobile manufacturer General Motors (GM) that designs and builds luxury vehicles. Its major markets are the United States, Canada, and China. Cadillac models are distributed i ...
's
Northstar Northstar may refer to: * Polaris, a star Arts and entertainment * Northstar (band), an emo band from Alabama * Northstar (rap group), a rap group affiliated with the Wu-Tang Clan * "Northstar", a 2019 song by XXXTentacion from the album ''Bad Vi ...
series. Displacing in its basic form, the direct family line transitioned to
longitudinal Longitudinal is a geometric term of location which may refer to: * Longitude ** Line of longitude, also called a meridian * Longitudinal engine, an internal combustion engine in which the crankshaft is oriented along the long axis of the vehicle, ...
and
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. The current categorisation is that a supercharger is a form of forced induct ...
versions. Variants were used at
Oldsmobile Oldsmobile or formally the Oldsmobile Division of General Motors was a brand of American automobiles, produced for most of its existence by General Motors. Originally established as "Olds Motor Vehicle Company" by Ransom E. Olds in 1897, it produ ...
(as the Aurora L47 V8 and "Shortstar" LX5 V6), as well as in several top-end 2000s
Pontiac Pontiac may refer to: *Pontiac (automobile), a car brand *Pontiac (Ottawa leader) ( – 1769), a Native American war chief Places and jurisdictions Canada *Pontiac, Quebec, a municipality ** Apostolic Vicariate of Pontiac, now the Roman Catholic D ...
s and
Buick Buick () is a division of the American automobile manufacturer General Motors (GM). Started by automotive pioneer David Dunbar Buick in 1899, it was among the first American marques of automobiles, and was the company that established General ...
s. The related Northstar System was Cadillac's trademarked name for a package of performance features introduced in mid-1992 that coupled the 4T80E transmission, a 100,000 mile service interval, road sensing suspension, variable power steering, and 4-wheel
disc brake A disc brake is a type of brake that uses the calipers to squeeze pairs of pads against a disc or a "rotor" to create friction. This action slows the rotation of a shaft, such as a vehicle axle, either to reduce its rotational speed or to hol ...
s to the Division's high-output and high-torque Northstar engines. GM ceased production of the Northstar in 2011. The final cars to receive it, the Cadillac DTS,
Buick Lucerne The Buick Lucerne is a full-size car manufactured by General Motors from 2005 to 2011. Named for the city of Lucerne, Switzerland, it served as Buick's top-of-the-line sedan until it was replaced by the second generation Buick LaCrosse. History T ...
, and Cadillac STS, rolled off the line in 2011. It was replaced by the GM LS small-block OHV engine, used in newer Cadillac V8 models like the CTS-V, marking a step back to a simpler, more reliable pushrod engine design. These LS V8 engines were the only V8 engines used by Cadillac for the next eight years, until the clean sheet Blackwing V8 was introduced in 2018 in the 2019 Cadillac CT6-V. A Cadillac-exclusive, it was discontinued after just two years in early 2020.


Development and features

GM initiated what ultimately became the Northstar's design at Oldsmobile R&D some time in 1984 in anticipation of the advanced
dual overhead cam An overhead camshaft (OHC) engine is a piston engine where 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 combustion c ...
V8 engines to be introduced by European and Japanese competitors later in the decade. At that time, Cadillac was using the aluminum '' HT''
Overhead Valve An overhead valve (OHV) engine, sometimes called a ''pushrod engine'', is a piston engine whose valves are located in the cylinder head above the combustion chamber. This contrasts with earlier flathead engines, where the valves were located be ...
(OHV) V8 which GM pushed hastily into production because the CAFE standards for 1982 would preempt using 1981's V8-6-4. At the time it was GM's corporate policy not to pass the gas guzzler tax on to the consumer. Cadillac was developing new models which they hoped would compete against the best luxury cars from BMW,
Mercedes-Benz Mercedes-Benz (), commonly referred to as Mercedes and sometimes as Benz, is a German luxury and commercial vehicle automotive brand established in 1926. Mercedes-Benz AG (a Mercedes-Benz Group subsidiary established in 2019) is headquartere ...
, and Asian rivals like
Lexus is the luxury vehicle division of the Japanese automaker Toyota. The Lexus brand is marketed in more than 90 countries and territories worldwide and is Japan's largest-selling make of premium cars. It has ranked among the 10 largest Japanese ...
,
Acura Acura is the luxury vehicle, luxury and performance division of Japanese automaker Honda, based primarily in North America. The brand was launched in the United States and Canada on March 27, 1986, marketing luxury and performance automobiles. It ...
, and
Infiniti is the luxury vehicle division of the Japanese automaker Nissan. Infiniti officially started selling vehicles on November 8, 1989, in North America. The marketing network for Infiniti-branded vehicles included dealers in over 50 countries in ...
. GM developed a laundry list of items to be included in the Allanté and updated
Eldorado El Dorado (, ; Spanish for "the golden"), originally ''El Hombre Dorado'' ("The Golden Man") or ''El Rey Dorado'' ("The Golden King"), was the term used by the Spanish in the 16th century to describe a mythical tribal chief (''zipa'') or king o ...
and Seville STS, including sophisticated steering, braking, and suspension technologies, and an engine exclusive to "Cadillac" the Division's dealers were clamoring for. This group of features became known as the ''Northstar System''. Central to it was a high-tech V8 with the performance and sophistication to compete with an ever-expanding list of imported challengers. Capable of producing out of its displacement, the Northstar featured a cast aluminum 90° V8 block with bore spacing split into unitary upper and lower halves. The lower
crankcase In a piston engine, the crankcase is the housing 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, resulting in the fuel/a ...
assembly supported the
crankshaft A crankshaft is a mechanical component used in a piston engine to convert the reciprocating motion into rotational motion. The crankshaft is a rotating shaft containing one or more crankpins, that are driven by the pistons via the connecting ...
without conventional main bearing caps. An oil manifold plate with an integrated silicone gasket forms the oil gallery under this. A typical oil change used of oil. GM specified cast-iron
cylinder liner In a reciprocating engine, the cylinder is the space in which a piston travels. The inner surface of the cylinder is formed from either a thin metallic liner (also called "sleeve") or a surface coating applied to the engine block. A piston is se ...
s and the cast aluminum pistons included valve clearance. Northstar is an
interference engine An interference engine is a type of 4-stroke internal combustion piston engine in which one or more valves in the fully open position extends into any area through which the piston may travel. By contrast, in a non-interference engine, the piston ...
: the valves will strike the pistons if they lose timing. It has bronze piston pin bushings and free-floating piston pins. GM used cast aluminum cylinder heads featuring 4 valves per cylinder. The heads used dual overhead cams driven through the "maintenance-free" cam-drive chain case. The cams act directly on
hydraulic lifters A hydraulic tappet, also known as a hydraulic valve lifter or hydraulic lash adjuster, is a device for maintaining zero valve clearance in an internal combustion engine. Conventional solid valve lifters require regular adjusting to maintain a sma ...
on the ends of the valves and are fed with a lubrication passage drilled through the cylinder head lengthwise. The intake valves are inclined at 25°, while the exhaust valves are canted to 7° with center-mounted platinum-tipped spark plugs. The cam covers are magnesium for light weight and sound damping.
Sequential fuel injection Fuel injection is the introduction of fuel in an internal combustion engine, most commonly automotive engines, by the means of an injector. This article focuses on fuel injection in reciprocating piston and Wankel rotary engines. All compr ...
was delivered via eight thermoplastic tubes. Ignition was distributorless, with a waste spark setup. The
powertrain control module A power-train control module, abbreviated PCM, is an automotive component, a control unit, used on motor vehicles. It is generally a combined controller consisting of the engine control unit (ECU) and the transmission control unit (TCU). On s ...
(PCM) controlled spark and fuel injection timing as well as the shift points for the new four-speed, transverse
GM 4T80 transmission The 4T80E is a series of automatic transmissions from General Motors Corporation, General Motors. Designed for transverse engine configurations, the series includes 4 forward gears. The 4Txx family is an evolution of the original Turbo-Hydramatic ...
. All engines of this family share the same Northstar bellhousing pattern. One notable feature advertised at the time was the "limp home" fail-safe mode, which allowed the engine to continue running for a limited time without any coolant. Supplying fuel to only one cylinder bank in turn, the engine would "air cool" the inactive bank. This technique, combined with its all-aluminum construction and large oil capacity, allows the engine to maintain safe temperatures, allowing a Northstar-equipped car to be driven with no coolant for about without damage. Another unusual feature of some heavily electronic-laden Northstar-equipped cars such as the
Seville Seville (; es, Sevilla, ) is the capital and largest city of the Spanish autonomous community of Andalusia and the province of Seville. It is situated on the lower reaches of the River Guadalquivir, in the southwest of the Iberian Peninsula ...
, DeVille, and
Eldorado El Dorado (, ; Spanish for "the golden"), originally ''El Hombre Dorado'' ("The Golden Man") or ''El Rey Dorado'' ("The Golden King"), was the term used by the Spanish in the 16th century to describe a mythical tribal chief (''zipa'') or king o ...
is a liquid-cooled alternator. Although this was intended to prolong alternator life, GM reverted to a traditional air-cooled setup for 2001 to eliminate potential leak points and extraneous tubing. Later developments included direct coil-on-plug ignition, roller lifters, and
variable valve timing In internal combustion engines, variable valve timing (VVT) is the process of altering the timing of a valve lift event, and is often used to improve performance, fuel economy or emissions. It is increasingly being used in combination with varia ...
, which can vary intake by up to 40° and the exhaust by up to 50°. VVT was devised for the
longitudinal Longitudinal is a geometric term of location which may refer to: * Longitude ** Line of longitude, also called a meridian * Longitudinal engine, an internal combustion engine in which the crankshaft is oriented along the long axis of the vehicle, ...
LH2 Liquid hydrogen (LH2 or LH2) is the liquid state of the element hydrogen. Hydrogen is found naturally in the molecular H2 form. To exist as a liquid, H2 must be cooled below its critical point of 33  K. However, for it to be in a fully liq ...
version, and has not, to date, been used on the transverse front wheel drive engines due to packaging considerations.


Northstar series

The engine was introduced in mid-1992 in the 1993
Cadillac Allanté The Cadillac Allanté is a two-door, two-seater luxury roadster marketed by Cadillac from 1987 until 1993. It used a Cadillac chassis and running gear with a body built in Italy by coachbuilder Pininfarina. It was expensive to produce with ...
; in 1996 the Northstar became the standard engine on all Cadillacs except the Fleetwood, but is now phased out of all Cadillac models. The Northstar engine was used on all Northstar equipped Cadillacs while the Deville Concours, Eldorado ETC, Seville STS, and in 2000 the Deville DTS, were fitted with the version. The original Northstar Allanté also introduced the ''Northstar System'' which included
traction control A traction control system (TCS), also known as ASR (from german: Antriebsschlupfregelung, lit=drive slippage regulation), is typically (but not necessarily) a secondary function of the electronic stability control (ESC) on production motor vehicle ...
,
adaptive suspension An active suspension is a type of automotive suspension on a vehicle. It uses an onboard system to control the vertical movement of the vehicle's wheels relative to the chassis or vehicle body rather than the passive suspension provided by large s ...
, and
antilock brakes An anti-lock braking system (ABS) is a safety anti-skid braking system used on aircraft and on land vehicles, such as cars, motorcycles, trucks, and buses. ABS operates by preventing the wheels from locking up during braking, thereby maintainin ...
. Early Northstar required premium grade gasoline to run safely. The Northstar was sold exclusively by that name by Cadillac for over a decade before being introduced in the 2004-2005
Pontiac Bonneville The Pontiac Bonneville is an automobile built by Pontiac (automobile), Pontiac from 1957 until 2005. Bonnevilles were full-size car, full-sized, with the exception of a brief period of mid-size car, mid-size between 1982 and 1986. The brand was in ...
and 2006
Buick Lucerne The Buick Lucerne is a full-size car manufactured by General Motors from 2005 to 2011. Named for the city of Lucerne, Switzerland, it served as Buick's top-of-the-line sedan until it was replaced by the second generation Buick LaCrosse. History T ...
. However, the '' L47'' V8 Northstar variant was used in the
Oldsmobile Aurora The Oldsmobile Aurora is a luxury sports sedan, manufactured and marketed by General Motors from 1994 until 2003 over two generations — sharing platforms with Buick Riviera and using the Cadillac-derived G platform. At the time of product ...
and the 3.5L ''LX5'' V6 in the
Oldsmobile Intrigue The Oldsmobile Intrigue is a mid-size sedan that was manufactured from 1997 through 2002 by Oldsmobile. The Intrigue's design cues were first seen in 1995 with the Oldsmobile Antares concept car, being unveiled in production form in January 1996 ...
. The LH2 engine variant received a forged steel crankshaft in October 2003. The LD8 and L37 variants received a forged crankshaft for the 2006 model year. Cadillac had planned to introduce a
V12 V12 or V-12 may refer to: Aircraft * Mil V-12, a Soviet heavy lift helicopter * Pilatus OV-12, a planned American military utility aircraft * Rockwell XFV-12, an American experimental aircraft project * Škoda-Kauba V12, a Czechoslovak experim ...
Northstar this decade, likely for use in the
Escalade {{Unreferenced, date=May 2007 Escalade is the act of scaling defensive walls or ramparts with the aid of ladders. Escalade was a prominent feature of sieges in ancient and medieval warfare, and though it is no longer common in modern warfare, ...
, but economics and new CAFE standards killed the idea. Most Northstar engines produce , with power reaching as high as in the
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. The current categorisation is that a supercharger is a form of forced induct ...
LC3. The engines were revised for 2000 with
coil-on-plug ignition A distributor is an enclosed rotating switch used in spark-ignition internal combustion engines that have mechanically timed ignition. The distributor's main function is to route high voltage current from the ignition coil to the spark plugs ...
and roller follower valvegear for improved fuel economy and reduced emissions. Though power output did not change, this update made premium fuel merely recommended, rather than required. All but the supercharged Northstars displaced with a bore and stroke. For better head gasket sealing between cylinders, the supercharged version is de-bored to for a total displacement of . The block is believed to be capable of expansion up to 5.4 L, though no such engine has been produced. The Northstar was on the
Ward's 10 Best Engines 10 of the World's best engines is an annual list of the ten ''"''best''"'' automobile engines available in the U.S. market, that are selected by ''Ward's AutoWorld'' magazine. The list was started in 1994 for Model Year 1995, and has been drawn eve ...
list for 1995, 1996, and 1997.


Northstar System

The ''Northstar System'' was
Cadillac The Cadillac Motor Car Division () is a division of the American automobile manufacturer General Motors (GM) that designs and builds luxury vehicles. Its major markets are the United States, Canada, and China. Cadillac models are distributed i ...
's trademarked name for a package of automobile performance features introduced in mid-1992 on the 1993
Cadillac Allanté The Cadillac Allanté is a two-door, two-seater luxury roadster marketed by Cadillac from 1987 until 1993. It used a Cadillac chassis and running gear with a body built in Italy by coachbuilder Pininfarina. It was expensive to produce with ...
and later on the 1993
Seville Seville (; es, Sevilla, ) is the capital and largest city of the Spanish autonomous community of Andalusia and the province of Seville. It is situated on the lower reaches of the River Guadalquivir, in the southwest of the Iberian Peninsula ...
and
Eldorado El Dorado (, ; Spanish for "the golden"), originally ''El Hombre Dorado'' ("The Golden Man") or ''El Rey Dorado'' ("The Golden King"), was the term used by the Spanish in the 16th century to describe a mythical tribal chief (''zipa'') or king o ...
. The ''Northstar System'' included the following components: ** ''L37'' high-output and ** ''LD8'' high-torque and *
Variable valve timing In internal combustion engines, variable valve timing (VVT) is the process of altering the timing of a valve lift event, and is often used to improve performance, fuel economy or emissions. It is increasingly being used in combination with varia ...
(VVT), a continuously variable system throughout the rpm range, increasing fuel economy. : GM engines use the
double overhead cam An overhead camshaft (OHC) engine is a piston engine where 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 combustion cha ...
, varying both intake and exhaust for better performance. * GM 4T80-E 4-speed
automatic transmission An automatic transmission (sometimes abbreviated to auto or AT) is a multi-speed transmission used in internal combustion engine-based motor vehicles that does not require any input from the driver to change forward gears under normal driving c ...
* ''Road Sensing Suspension'' (RSS), which monitored damping rates of the shock absorbers every 15 milliseconds, selecting between two settings. : RSS was available in both standard and CV-RSS (continuously-variable) systems. * 4-wheel
disc brake A disc brake is a type of brake that uses the calipers to squeeze pairs of pads against a disc or a "rotor" to create friction. This action slows the rotation of a shaft, such as a vehicle axle, either to reduce its rotational speed or to hol ...
s with Bosch
antilock brakes An anti-lock braking system (ABS) is a safety anti-skid braking system used on aircraft and on land vehicles, such as cars, motorcycles, trucks, and buses. ABS operates by preventing the wheels from locking up during braking, thereby maintainin ...
* ''Magnasteer'' speed-variable
power steering A power steering is a mechanical device equipped on a motor vehicle that helps drivers steer the vehicle by reducing steering effort needed to turn the steering wheel, making it easier for the vehicle to turn or maneuver at lower speeds. Hydraul ...
, which combines conventional hydraulic power steering and magnetized "doughnuts" mounted around the output shaft, which stiffen the steering as vehicle speed increases. Later versions of the Northstar engine included the 4.6L and ''LH2'' which began in 2004, and supercharged 4.4L ''LC3'' created for the STS-V which are detailed below.


L37

The L37 ( VIN "9") was the original Northstar. It is tuned for responsiveness and power, while the later LD8 is designed for more sedate use. The L37 code had been used on all high-output
transverse Transverse may refer to: *Transverse engine, an engine in which the crankshaft is oriented side-to-side relative to the wheels of the vehicle *Transverse flute, a flute that is held horizontally * Transverse force (or ''Euler force''), the tangen ...
Northstars, even as the exact engine specifications evolved. The compression ratio for the L37 is 10.3:1 for engines built prior to 2000, and 10.0:1 afterwards. The original L37 was specified at , but 1993 production examples were rated at . The engine topped out at from 1996 through 2004 on the
STS STS, or sts, may refer to: Medicine * Secondary traumatic stress, a condition which leads to a diminished ability to empathize * Sequence-tagged site, a gene-reference in genomics * Soft-tissue sarcoma * Staurosporine, an antibiotic * STS (gen ...
, DTS and
ETC * Etc. or et cetera, a Latin expression meaning "and the other things" or "and the rest". ETC or etc may also refer to: Companies and organizations * ETC (Chilean TV channel), a Chilean cable television channel * ETC (Philippine TV channel), a P ...
models, making these some of the most powerful domestic front wheel drive cars ever built. For 2005 the high output Northstar became Northstar NHP, and was downrated to under the new SAE certified horsepower rating system. In 2006, the updated DTS "Performance Package" model got a slight bump to . Vehicles using the L37 include:


LD8

The LD8 (VIN "Y") is a
transverse Transverse may refer to: *Transverse engine, an engine in which the crankshaft is oriented side-to-side relative to the wheels of the vehicle *Transverse flute, a flute that is held horizontally * Transverse force (or ''Euler force''), the tangen ...
V8 for
front-wheel drive Front-wheel drive (FWD) is a form of engine and transmission layout used in motor vehicles, where the engine drives the front wheels only. Most modern front-wheel drive vehicles feature a transverse engine, rather than the conventional longit ...
cars. Introduced in 1994, it is designed to provide more torque than the high-revving L37. The LD8 code had been used on all torque-tuned transverse Northstars, even as the exact engine specifications evolved. Compression ratio is 10.3:1 for engines built prior to model year 2000, and 10.0:1 for those built afterwards. The 1998 revision is quieter than previous Northstar engines, due to hydraulic engine mounts, and performs better due to a tuned intake system. Most LD8 Northstars are rated at and .


LH2 (VIN "A")

The Northstar was designed originally for transverse
front-wheel drive Front-wheel drive (FWD) is a form of engine and transmission layout used in motor vehicles, where the engine drives the front wheels only. Most modern front-wheel drive vehicles feature a transverse engine, rather than the conventional longit ...
applications. It was modified substantially in 2004 for
longitudinal Longitudinal is a geometric term of location which may refer to: * Longitude ** Line of longitude, also called a meridian * Longitudinal engine, an internal combustion engine in which the crankshaft is oriented along the long axis of the vehicle, ...
rear- and
all-wheel drive An all-wheel drive vehicle (AWD vehicle) is one with a powertrain capable of providing power to all its wheels, whether full-time or on-demand. The most common forms of all-wheel drive are: ;1x1 : All unicycles Reflecting one axle with one w ...
use in the
STS STS, or sts, may refer to: Medicine * Secondary traumatic stress, a condition which leads to a diminished ability to empathize * Sequence-tagged site, a gene-reference in genomics * Soft-tissue sarcoma * Staurosporine, an antibiotic * STS (gen ...
, SRX, and XLR, as well as receiving continuously variable valve timing on both intake and exhaust sides. The RWD (LH2) Northstar produces and . The addition of variable valve timing enables most of the increase in power from the L37 and LD8 Northstars.


LC3

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. The current categorisation is that a supercharger is a form of forced induct ...
Northstar was used in the 2006 Cadillac STS-V and
Cadillac XLR-V The Cadillac XLR is a front-engine, rear-drive, two passenger roadster manufactured and marketed by Cadillac from 2003 to 2009 across a single generation — and noted for its power retractable hardtop, Bulgari designed interior instruments ...
. The bore was reduced for increased strength and improved head gasket sealing.
Variable valve timing In internal combustion engines, variable valve timing (VVT) is the process of altering the timing of a valve lift event, and is often used to improve performance, fuel economy or emissions. It is increasingly being used in combination with varia ...
is used on both the intake and exhaust sides. The STS-V engine produces at 6400 rpm and at 3900 rpm with 9.0:1 compression and the XLR-V engine produces at 6400 rpm and at 3900 rpm.


L47

The L47 Aurora engine was a special V8 designed for the
Oldsmobile Aurora The Oldsmobile Aurora is a luxury sports sedan, manufactured and marketed by General Motors from 1994 until 2003 over two generations — sharing platforms with Buick Riviera and using the Cadillac-derived G platform. At the time of product ...
, based on the Northstar engine, used during the 1995-1999 and 2001-2003 model years. It is a DOHC V8 which produced and of torque. The bore and stroke was . The L47 had a 10.3:1 compression ratio and used premium fuel. Although most of the Northstar's features, including the coolant loss system, remained intact, the decreased bore increased weight unacceptably. To reduce it, Oldsmobile used a one-piece glass-filled thermoplastic
intake manifold In automotive engineering, an inlet manifold or intake manifold (in American English) is the part of an engine that supplies the fuel/air mixture to the cylinders. The word ''manifold'' comes from the Old English word ''manigfeald'' (from the ...
and simplified AC Rochester sequential fuel injection. A new die-cast structural aluminum oil pan incorporated baffling to reduce oil starvation in hard driving. A starter interlock prevented the starter from engaging if the quiet L47 was already running. An early version or
prototype A prototype is an early sample, model, or release of a product built to test a concept or process. It is a term used in a variety of contexts, including semantics, design, electronics, and Software prototyping, software programming. A prototyp ...
of this engine was used in the 2nd generation
Oldsmobile Aerotech The Oldsmobile Aerotech was a series of experimental high-speed vehicles manufactured between 1987 and 1992 incorporating the latest in performance technology with the intention of breaking multiple automobile speed records. The first such c ...
. A highly modified version of this engine was used by General Motors racing division initially for
IMSA The International Motor Sports Association (IMSA) is a North American sports car racing sanctioning body based in Daytona Beach, Florida under the jurisdiction of the ACCUS arm of the FIA. It was started by John Bishop, a former executive direc ...
sports car competition in an Oldsmobile Aurora GTS-1 and Riley&Scott LMP prototypes in 1995,
Indy Racing League The IndyCar Series, currently known as the NTT IndyCar Series under sponsorship, is the highest class of regional North American open-wheel single-seater formula racing cars in the United States, which has been conducted under the auspices of ...
competition starting in 1997, then was later used in the Cadillac Northstar LMP program in 2000. Both engines retained the 4.0 L displacement, but the Northstar LMP version was twin-turbocharged.Weitzman, Larry (2001
The Aurora by Oldsmobile (2001), Better in every respect
''Autochannel''. Retrieved on June 28, 2009.
The Aurora was also used in the
Shelby Series 1 Shelby Series 1 is a high-performance roadster designed by Carroll Shelby and produced by Shelby American. It was powered by Oldsmobile's 4.0 L '' L47 Aurora'' V8 DOHC engine. It has base hp of 320 (324 PS) at 6500 rpm, at 5000 rpm and will do ...
car. In the inaugural DTM season, Opel would debut their Astra with a V8 derived from the L47. The Aurora engine was introduced in 1994 for the 1995 model year, and
General Motors The General Motors Company (GM) is an American Multinational corporation, multinational Automotive industry, automotive manufacturing company headquartered in Detroit, Michigan, United States. It is the largest automaker in the United States and ...
has not used this engine since the retirement of Oldsmobile in 2004.


LX5 (Shortstar)

The LX5 is a DOHC V6 from
Oldsmobile Oldsmobile or formally the Oldsmobile Division of General Motors was a brand of American automobiles, produced for most of its existence by General Motors. Originally established as "Olds Motor Vehicle Company" by Ransom E. Olds in 1897, it produ ...
, introduced in 1999 with the
Intrigue Intrigue may refer to: TV and film * ''Intrigue'' (1920 film), a 1920 German silent drama film * ''Intrigue'' (1942 film), a Spanish film * ''Intrigue'' (1947 film), 1947 film directed by Edwin L. Marin * ''The Intrigue'', 1916 silent film dra ...
. It was produced by the ''Premium'' engine group at GM and was thus called the Premium V6, or PV6, while it was being developed. It is based on the L47 Aurora V8, which is itself based on the Northstar engine, so engineers called it the Short North, though Oldsmobile fans have taken to calling it the Shortstar. Although it has a 90° V-angle like the Northstar, the engine block was engineered from scratch, so bore centers are different. It has chain-driven
dual overhead cam An overhead camshaft (OHC) engine is a piston engine where 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 combustion c ...
s and four valves per cylinder, but is an even-firing design with a split-pin crankshaft similar to the Buick 3800 engine. The LX5 displaced and produced at 5,600 rpm and at 4,400 rpm. Bore and stroke is . It was also one of GM's first engines to use coil-on-plug ignition. Compression ratio is 9.3:1. The cost of building this engine was high, and it was not used in many vehicles. It was said at the time that a family of premium V6s would follow, with displacements ranging from 3.3 L to 3.7 L, but only the LX5 was ever produced before GM discontinued the Shortstar in favor of their current flagship V6, the High Feature engine, in 2004. The LX5 was entirely different from any other V6 in the GM inventory - the only other DOHC V6 engines ever offered by GM included the Chevrolet Twin Dual Cam produced from 1991-1997, which was made by modifying the traditional Chevy 60-degree OHV block V6 for the dual overhead cams rather than building a DOHC engine from the ground up, and the Cadillac/Holden HFV6 available from 2004 to the present day. These three designs are completely unrelated and leave two gaps in 1998 and 2003 where no DOHC V6 was available from GM (except for the 54 degree Opel V6 used most notably in the first generation Cadillac CTS at launch as well as the Saturn L Series and Catera). This contrasts starkly with competitors practices of evolving engineering over multiple, continuously improving designs. As with the Aurora V8, production stopped with the demise of Oldsmobile. The 3.5L LX5 was on the
Ward's 10 Best Engines 10 of the World's best engines is an annual list of the ten ''"''best''"'' automobile engines available in the U.S. market, that are selected by ''Ward's AutoWorld'' magazine. The list was started in 1994 for Model Year 1995, and has been drawn eve ...
list for 1999 and 2000.


See also

* GM 60-degree DOHC V6 engine *
GM High Feature engine The GM High Feature engine (also known as the HFV6, and including the 3600 LY7 and derivative LP1) is a family of modern General Motors DOHC V6 engines. The series was introduced in 2004 with the Cadillac CTS and the Holden Commodore (VZ). It is a ...
*
Cadillac V8 engine The term Cadillac V8 may refer to any of a number of V8 engines produced by the Cadillac Division of General Motors since it pioneered the first such mass-produced engine in 1914. Most commonly, such a reference is to one of the manufacturer's ...
*
GM Ultra Engine Ultra was the codename for General Motors' next-generation family of DOHC V8 engines that was being developed to replace the Northstar as the V8 engine of choice for GM's premium vehicles. There is very little information on the engine's specifica ...
*
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 we ...


Notes


References

* * *


External links

*
Technical article from AutoSpeed

Wiebe Patent #8,740,532, Cylinder Head Stud Kit for the Northstar engine
{{DEFAULTSORT:Northstar Buick engines Cadillac engines Automotive technology tradenames 1992 introductions V6 engines V8 engines Gasoline engines by model