Difference between revisions of "GM LS engine"

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{{Infobox Automobile engine
{{Infobox Automobile engine
|name=GM LS engine
|name=GM Premium V
|aka=[[GM Vortec engine]]
|aka=Cadillac Northstar
|image=
|manufacturer=[[General Motors Corporation|General Motors]]
|manufacturer=[[General Motors]]
|production=1991–
|production=1997–present
|class=[[DOHC]] 90° [[V8]]/[[V6]]
|class=[[OHV]] [[V8 engine|V8]]
|predecessor=[[Cadillac V8 engine#Aluminum OHV|Cadillac HT V8]]<br />[[GM 60-Degree V6 engine#LQ1|LQ1 V6]]
|predecessor=[[GM LT engine]], [[Chevrolet Small-Block engine]], [[Chevrolet Big-Block engine]]
|similar=[[Jaguar AJ-V8 engine|Jaguar AJ-V8]]<br />[[Ford Modular engine|Ford Modular V8]]<br />[[Ford Yamaha V8 engine|Ford/Yamaha V8]]<br />[[Chrysler PowerTech engine|Chrysler PowerTech V8]]<br />[[Mercedes-Benz M113 engine|Mercedes-Benz M113/M115]]<br />[[BMW M62|BMW M62/S62]]<br />[[BMW N62]]<br />[[Toyota UZ engine|Toyota UZ]]<br />[[Nissan VH engine|Nissan VH]]<br />[[Nissan VK engine|Nissan VK]]
|successor=
|similar=[[Ford Modular engine]]<br>[[Chrysler Hemi engine]]<br>[[Chrysler PowerTech engine|Chrysler PowerTech V8]]<br>[[Nissan VH engine|Nissan VH]]<br>[[Nissan VK engine|Nissan VK]]<br>[[Toyota UZ engine|Toyota UZ]]
}}
}}
The '''Premium V''' family of [[automobile]] [[piston engine|engines]] is [[General Motors Corporation|General Motors]]' modern 90° [[v engine]] architecture. The family is most associated with [[Cadillac (automobile)|Cadillac]]'s '''[[#Northstar|Northstar]]''' [[V8]], but the family has also seen use at [[Oldsmobile]] (as the '''[[#L47|Aurora L47]]''' V8 and '''[[#LX5|"Shortstar" LX5]]'''). The Oldsmobile variants are no longer in production, but the Northstar family has expanded with new [[longitudinal engine|longitudinal]] and 4.4&nbsp;L [[supercharged]] versions. The Northstar name is now used outside Cadillac as well, with the [[Pontiac]] and [[Buick]] versions now carrying that moniker. [[Alfa Romeo]] is rumored to be another future user of the Premium V in the [[United States|US]]-market [[Alfa Romeo Kamal|Kamal]].


The '''LS''' series  is a new design intended as the only V-8 engine utilized in [[General Motors Corporation|General Motors]]' line of RWD cars and trucks. The LS series was a clean sheet design with little in common with the classic [[Chevrolet Small-Block engine|Chevrolet small block V8]].  The LS is all-[[aluminum]] and has 6-bolt main [[bearing]] caps.  
== Development and features ==
The Premium V design was initiated as a response to the advanced [[DOHC|dual overhead cam]] [[V8]] engines introduced by European and Japanese competitors of [[Cadillac]] in the late 1980s. At that time, Cadillac was using the aluminum ''[[Cadillac V8 engine#Aluminum OHV|HT]]'' [[pushrod engine|Overhead Valve]] (OHV) V8 which had been pushed hastily into production after the failure of the [[Cadillac V8 engine#368 and V8-6-4|V8-6-4]] of 1981.


The LS engine has been the sole powerplant of the [[Chevrolet Corvette]] since 1997 and has seen use in a wide variety of other General Motors vehicles, ranging from [[Pontiac Firebird|sport coupes]] to [[Chevrolet Silverado|full size trucks]]. Due to the engine's relatively compact external dimensions compared to its displacement and power output, the engine family is also a popular choice for [[kit car]]s, [[hot rod]]s and even [[light aircraft]].
Cadillac was developing new models like the [[Cadillac Allanté|Allanté]] and updated [[Cadillac Eldorado|Eldorado]] and [[Cadillac Seville|Seville STS]] which they hoped would compete against the best from [[BMW]], [[Mercedes-Benz]], [[Lexus]], and [[Infiniti]]. They developed a laundry list of items that must be included in these new models, including sophisticated steering, braking, and suspension technologies, which became known as the [[Northstar System]]. One key element was a high-tech V8 engine with all of the features and performance of the competitors' offerings.


==Generation III==
The "Northstar" V8, as it was then known, was an evolution of the [[Lotus Cars|Lotus]]-designed  [[GM LT engine#LT5|Chevrolet LT5]] all-aluminum [[DOHC]] [[multi-valve|32-valve]] V8 used in the [[Chevrolet Corvette C4#ZR-1|Corvette ZR-1]].  Archrival [[Ford Motor Company]] was developing a similar engine at that time as well, and Ford's [[Ford Modular engine|Modular engine]] would precede the Northstar into production with its introduction on the 1991 [[Lincoln Town Car]]. Both continue in production at 4.6&nbsp;L of displacement.
The '''Generation III''' V-8 engines replaced the [[GM LT engine|LT family]] in 1997. These shared the same [[bore]] spacing (4.4") as their [[cast iron]] predecessors but almost everything else was changed. The bore was reduced to 3.9&nbsp;in and the [[stroke]] longer at 3.62&nbsp;in. The engine blocks were cast in aluminum for car applications, and iron for most truck applications (notable exceptions include the [[Chevrolet TrailBlazer]]).  The engine also introduced [[Distributor#Direct ignition|coil-on-plug]] ignition. The traditional five-bolt pentagonal cylinder head pattern was replaced with a square four-bolt design, and the pistons are of the flat-topped variety. The cylinder [[firing order]] was changed to 1-8-7-2-6-5-4-3, so that the LS series now corresponds to the firing pattern of other modern V8 engines (for example the [[Ford Modular engine|Ford Modular V8]]).


===LS1===<!-- This section is linked from [[Chevrolet Camaro]] -->
Capable of producing {{Convert| 300|hp|kW|0|abbr=on}}, the Northstar featured a unique die-cast aluminum 90° V8 block with 102&nbsp;mm (4&nbsp;in) bore spacing split into unitary upper and lower halves. The lower crankcase assembly supported the crankshaft without conventional main bearing caps. An oil manifold plate with an integrated silicon gasket forms the oil gallery under this. A typical oil change used {{convert|8.5|U.S.qt|impqt|lk=on}}.
[[Image:1998ChevroletCamaroZ28-engine.jpg|right|thumb|250px|GM LS1 engine from the [[Chevrolet Camaro]]]]


The '''LS1''' shares little other than similar displacement, external dimensions, and rod bearings, with its [[Chevrolet Small-Block engine| predecessor]]. It is an all-aluminum 5.7&nbsp;L ({{convert|5665|cc|CID|disp=s|abbr=on}}) [[pushrod]] engine and was rated between 305 - 350&nbsp;hp (227 to 261&nbsp;kW) and 335-375&nbsp;ft·lbf (454-508&nbsp;N·m) of [[torque]] in North America, depending on the application.  In Australia, continuous modifications were made to the LS1 engine throughout its lifetime, reaching 382&nbsp;hp (285&nbsp;kW) in the [[Holden Special Vehicles|HSV's]] YII series and a [[Callaway Cars Incorporated|Callaway]] modified version, named C4B, was fitted to HSV GTS models producing 402&nbsp;hp (300&nbsp;kW).  
Cast-iron cylinder liners were specified and the forged aluminum pistons included valve clearance, making Northstar a non-interference engine, with bronze pin bushings and free-floating piston pins used.


The version fitted to the 2004 Pontiac GTO was rated at 350&nbsp;hp (261&nbsp;kW) and 365&nbsp;ft·lbf (494&nbsp;Nm) of torque. Beginning in 2001, the LS1 in the Corvette received the higher-flowing intake from the LS6 and a milder [[camshaft]] to keep power at the same level; this also allowed GM to remove the [[exhaust gas recirculation]] (EGR) system (Camaro/Firebird only; 97-00 Corvette LS1 never used an EGR system). The block is very similar to that of the higher-output LS6; beginning in 2002, some LS1 engines were actually built using the LS6 block instead. {{Fact|date=August 2008}} The LS1 was on the [[Ward's 10 Best Engines]] list for 1998.
The one-piece cast aluminum cylinder heads extend around the "maintenance-free" cam-drive chain case. Direct-acting hydraulic valves are used 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 were fabricated from magnesium for light weight.
* 1997-2004 [[Chevrolet Corvette C5]], excluding Z06
* 1998-2002 [[Chevrolet Camaro]] Z28, SS
* 1998-2002 [[Pontiac Firebird]] Formula, Trans Am, Trans Am WS6
* 2004 [[Pontiac GTO]]
* 1999-2005 [[Holden Commodore Ute]]
* 1999-2005 [[Holden Commodore]] ([[Holden VT Commodore|VT]], [[Holden VX Commodore|VX]], [[Holden VY Commodore|VY]], [[Holden VZ Commodore|VZ]])
* 1999-2005 [[Holden Statesman]] ([[Holden WH Statesman|WH]], [[Holden WK Statesman|WK]], [[Holden WL Statesman|WL]])
* 1999-2005 [[Holden Caprice]] ([[Holden WH Caprice|WH]], [[Holden WK Caprice|WK]], [[Holden WL Caprice|WL]])
* 1999-2004 [[Holden Special Vehicles]] (all V8 models)
* 2001-2005 [[Holden Monaro]] ''CV8''
* 2006-2007 [[Elfin MS8 Streamliner]]


===LS6===
Eight thermoplastic tubes were used in the induction system, leading to sequential fuel injection. Direct ignition was a novelty for the time, with an electronic system adjusting spark and fuel injection timing as well as the shift points for the new [[GM 4T80 transmission|4T80-E]] transmission.
[[Image:Chevrolet Corvette C5 Z06 LS6 engine.jpg|right|thumb|250px|GM LS6 engine in a [[Chevrolet Corvette]] Z06]]


:''LS6 can also refer to a 454&nbsp;CID [[Chevrolet Big-Block engine]] of the 1970s''
One notable feature, advertised at the time, was the fail-safe cooling mode which allowed the engine to continue running for a limited time without any coolant at all. It alternated banks of cylinders, basically "air cooling" the inside of the cylinders, to maintain cool temperatures, allowing a Northstar-equipped car to be driven with no coolant for about 100&nbsp;mi (161&nbsp;km) with no damage.


The '''LS6''' is a higher-output version of GM's LS1 engine and retains the same capacity. The initial 2001 LS6 produced 385&nbsp;hp (287&nbsp;kW) and 385&nbsp;ft·lbf (522&nbsp;N·m), but the engine was modified for 2002 through 2004 to produce 405&nbsp;hp (302&nbsp;kW) and 400&nbsp;ft·lbf (542&nbsp;N·m) of torque. The LS6 was originally only used in the high-performance C5 [[Chevrolet Corvette|Corvette]] Z06 model, with the [[Cadillac CTS V-Series]] getting the 400&nbsp;hp engine later. The V-Series used the LS6 for two years before being replaced by the LS2 in 2006. For 2006, the Z06 replaced the LS6 with the new 7.0L [[GM LS engine#LS7|LS7]].
Another unusual feature of some Northstar-equipped cars is a liquid-cooled alternator used on Cadillac's [[Cadillac Seville|Seville]], [[Cadillac DeVille|DeVille]], and [[Cadillac Eldorado|Eldorado]]. The liquid-cooling helped prolong the life of the alternator in these electronic-laden models, though GM reverted to a traditional air-cooled setup for 2001 to eliminate potential leak points and extraneous tubing.


The LS6 shares its basic block architecture with the [[GM LS1 engine]], but other changes were made to the design such as windows cast into the block between cylinders, improved main web strength and bay to bay breathing, an intake manifold and MAF-sensor with higher flow, a camshaft with higher lift and more duration, a higher compression ratio and a revised oiling system better suited to high lateral acceleration. <ref>[http://www.idavette.net/hib/ls6/page3.htm Corvette LS6 - Ruthless Pursuit of Power<!-- Bot generated title -->]</ref>
All engines of this family share the same [[List of GM bellhousing patterns#Northstar pattern|Northstar bellhousing pattern]].


The casting number, located on the top rear edge of the block, is 12561168.
Later developments included [[variable valve timing]], which can vary intake by up to 40° and the exhaust by up to 50°. This system was devised for the [[longitudinal engine|longitudinal]] [[#LH2|LH2]] version, and has not, to date, been used on the transverse front wheel drive engines due to packaging considerations.


Applications:
* 2001-2004 [[Chevrolet Corvette C5 Z06]]
* 2004-2005 [[Cadillac CTS V-Series]]


==Generation IV==
== Northstar ==
In 2004, the Generation III was superseded by the '''Generation IV'''. This category of engines has provisions for high-displacement ranges up to 7.0&nbsp;L and power output to {{Convert|638|hp|kW|0|abbr=on}}. Building upon the Generation III design, Generation IV was designed with [[displacement on demand]] in mind, a technology that allows 4 cylinders in alternating fashion from side to side and front to back to be deactivated. It can also accommodate [[variable valve timing]].  A 3-[[poppet valve|valve]] per cylinder design was originally slated for the LS7, which would have been a first for a GM [[pushrod]] engine; but the idea was shelved owing to design complexities and when the same two-valve configuration as the other Generation III and IV engines proved to be sufficient to meet the goals for the LS7. It has been reported that the LS3 and an upcoming 6.0&nbsp;L Vortec engine represent the final two designs to be considered in the Generation IV engine family, and that future designs — expected around 2009 — will be part of the Generation V engine family.<ref name='Wards Auto 2007-08-30'>{{cite web | first=Mike | last=Sutton | title=GM Reveals Small-Block V-8 With Direct Injection | date=2007-08-29 | url=http://subscribers.wardsauto.com/ar/gm_reveals_v-8/wall.html?return=http://subscribers.wardsauto.com/ar/gm_reveals_v-8/index.html | work =WardsAuto.com | accessdate = 2007-08-30}}</ref>
The engine was introduced in mid-1992 in the 1993 [[Cadillac Allanté]] and continues to be used in most Cadillac models. The original Northstar Allanté also introduced the '''[[Northstar System]]''' which included [[traction control]], [[adaptive suspension]], and [[antilock brakes]]. Early Northstar had no knock sensors, and required premium grade gasoline to run safely.


===LS2===<!-- This section is linked from [[Chevrolet Camaro]] -->
The Northstar was sold exclusively by Cadillac for over a decade before being introduced in the 2004 [[Pontiac Bonneville]] and 2006 [[Buick Lucerne]]. However, the 4.0L [[#L47|''L47'']] V8 variant was used in the [[Oldsmobile Aurora]] and the [[GM Premium V engine#LX5|3.5L ''LX5'']] V6 in the [[Oldsmobile Intrigue]]. The engine received a forged steel crankshaft in 2003. Cadillac had planned to introduce a [[V12]] Northstar this decade, likely for use in the [[Cadillac Escalade|Escalade]], but economics and new CAFE standards have killed this idea.
[[Image:GM LS2 engine.jpg|right|thumb|250px|GM LS2 engine in a 2005 [[Chevrolet Corvette C6|Chevrolet Corvette]]]]


The '''LS2''' was introduced as the Corvette's new base engine for the 2005 model year. It produces {{Convert|400|hp|0|abbr=on}} at 6000&nbsp;rpm and {{Convert|400|ft.lbf|0|abbr=on}} at 4400&nbsp;rpm from a slightly larger displacement of 6.0&nbsp;L ({{convert|5967|cc|CID|disp=s|abbr=on}}). It is similar to the high-performance LS6, but with an improved power peak and more torque throughout the rpm range. The LS2s in the E-series HSVs are modified in Australia to produce {{Convert|412|hp|0|abbr=on}} and {{Convert|412|ft·lbf|0|abbr=on}}. The LS2s in the Buick Rainier, Chevrolet Trailblazer SS, and the Saab 9-7X Aero are rated at 395 hp (295 kW) and 400 lb·ft (540 N·m) of torque.
Most Northstar engines produce {{Convert|275|hp|kW|0|abbr=on}} to {{Convert|315|hp|kW|0|abbr=on}}. The engines were revised for 2000 with [[coil-on-plug ignition]] and roller follower valvegear for improved [[fuel economy]] and reduced emissions. Though power output did not change, this update eliminated the need for premium fuel.


All but the supercharged Northstar displace {{Auto Lrev|279}} with a {{Auto mm|93}} bore and {{Auto mm|84}} stroke. For better head gasket sealing between cylinders, the [[supercharged]] version is de-bored to {{Auto mm|91}} for a total displacement of {{Auto Lrev|266}}. The block is said{{Who?|date=September 2008}} to be capable of expansion up to 5.4&nbsp;L, though no such engine has been produced.


The Northstar was on the [[Ward's 10 Best Engines]] list for 1995, 1996, and 1997.


Applications:
=== L37 ===
* 2005-2007 [[Buick Rainier]]
The '''L37''' (VIN "9") was the original Northstar. It is tuned for responsiveness and power, while the later [[#LD8|LD8]] is designed for more sedate use. The L37 code has been used on all high-output [[transverse engine|transverse]] Northstars, even as the exact engine specifications evolved. Compression ratio for the L37 is 10:1, shared with the LD8.


* 2006-2007 [[Cadillac CTS-V]]
The original L37 was specified at {{Convert|290|hp|kW|0|abbr=on}}, but 1993 production examples were rated at {{Convert|295|hp|kW|0|abbr=on}}. The engine topped out at {{Convert|300|hp|kW|0|abbr=on}} from 1996 through 2004 on the [[Cadillac Seville|STS]], [[Cadillac Deville|DTS]] and [[Cadillac Eldorado|ETC]] models, making these some of the most powerful domestic front wheel drive cars ever built, the most powerful title still belonging to the 1970 [[Cadillac Eldorado]] {{Auto CID|500}} with {{Convert|400|hp|kW|0|abbr=on}} (although the latter's rating is in the older [[SAE]] [[horsepower#SAE gross horsepower|gross horsepower]] system, figured without accessories or muffler, where the current engine outputs are as-installed, net ratings). For 2005 the high output Northstar became Northstar NHP, and was downrated to {{convert|290|hp|kW}} under the new [[Horsepower|SAE certified horsepower]] rating system. In 2006, the updated DTS "Performance Package" model got a slight bump to {{Convert|292|hp|kW|0|abbr=on}}.
* 2005-2007 [[Chevrolet Corvette C6|Chevrolet Corvette]]
* 2005-2006 [[Chevrolet SSR]]
* 2006-2009 [[Chevrolet TrailBlazer]] ''SS''
* 2004-2007 [[Holden Special Vehicles]] (all V8 models)
* 2005-2006 [[Pontiac GTO]]
* 2008-2009 [[Saab 9-7X]] Aero
* 2005-2006 [[Vauxhall Monaro VXR]]


===L76===
Vehicles using the L37 include:
:''See also the [[GM Vortec engine#L76|Vortec 6000 L76]]''
{| class=wikitable
'''L76''' was originally [[Holden]]'s version of the 6.0&nbsp;L ({{convert|5967|cc|CID|disp=s|abbr=on}}) Generation IV engine. While displacement on demand technology was disabled on Holdens, this feature is enabled on the 2008 [[Pontiac G8]] and subsequently re fitted in the 2009 model Holdens with AFM enabled, but only on models fitted with the 6L80 Automatic Transmission.  The engine also meets [[Euro III]] emissions requirements. Output is 348&nbsp;hp (260&nbsp;kW) at 5600&nbsp;rpm and 376&nbsp;ft·lbf (510&nbsp;N·m) at 4400&nbsp;rpm for the Holden variant, and 361&nbsp;hp (269.8&nbsp;kW) and 385&nbsp;ft·lbf of torque (526.5&nbsp;N·m) for the G8 GT.<ref name='Global Auto Index G8 Article'>{{cite web | title= All-new G8 accelerates new era of rear-wheel-drive performance at Pontiac| date= 2007-02-07| url= http://www.globalautoindex.com/news.plt?no=1735| work = Global Auto Index| accessdate = 2007-08-30}}</ref>
!Year
!Model
!Power
!Torque
|-
|1993||[[Cadillac Allanté]]||{{Convert|295|hp|kW|0|abbr=on}}||{{Auto lbft|290}}
|-
|1993-1994||[[Cadillac Eldorado]] ''ETC''||{{Convert|295|hp|kW|0|abbr=on}}||{{Auto lbft|290}}
|-
|1995–2002||[[Cadillac Eldorado]] ''ETC''||{{Convert|300|hp|kW|0|abbr=on}} @ 6000&nbsp;rpm||{{Auto lbft|295}} @ 4400&nbsp;rpm
|-
|1993||[[Cadillac Seville]] ''STS''||{{Convert|295|hp|kW|0|abbr=on}}||{{Auto lbft|290}}
|-
|1994–2004||[[Cadillac Seville]] ''STS''||{{Convert|300|hp|kW|0|abbr=on}} @ 6000&nbsp;rpm||{{Auto lbft|295}} @ 4400&nbsp;rpm
|-
|1996–2004||[[Cadillac DeVille]] ''Concours/DTS''||{{Convert|300|hp|kW|0|abbr=on}} @ 6000&nbsp;rpm||{{Auto lbft|295}} @ 4400 RPM
|-
|2005||[[Cadillac DeVille]] ''DTS''||{{Convert|290|hp|kW|0|abbr=on}} @ 5600&nbsp;rpm||{{Auto lbft|285}} @ 4400&nbsp;rpm
|-
|2006–||[[Cadillac DTS]] ''Performance''||{{Convert|292|hp|kW|0|abbr=on}} @ 6300&nbsp;rpm||{{Auto lbft|288}} @ 4500&nbsp;rpm
|-
|2008-||[[Buick Lucerne#The Lucerne Super|Buick Lucerne]] ''Super''||{{Convert|292|hp|kW|0|abbr=on}} @ 6300&nbsp;rpm||{{Auto lbft|288}} @ 4500&nbsp;rpm
|}


Applications:
=== LD8 ===
* 2006 [[Holden VZ Commodore]]
The '''LD8''' (VIN "Y") is a [[transverse engine|transverse]] [[V8]] for [[front-wheel drive]] cars. Introduced in 1994, it is designed to provide more torque than the high-revving [[#L37|L37]]. The LD8 code has been used on all torque-tuned [[transverse engine|transverse]] Northstars, even as the exact engine specifications evolved. Compression ratio is 10:1.
* 2008 [[Pontiac G8]]
* 2009 [[Holden VE Commodore]]
* 2009 [[Holden WM Statesman]] / [[Holden WM Caprice]]
* 2009 Holden VE UTE


===L98===
The 1998 revision is quieter than previous Northstar engines, due to hydraulic engine mounts, and performs better due to a tuned intake system.  
:''For the tuned-port Generation I engine of the same RPO, see [[Chevrolet Small-Block engine#L98|Chevrolet L98]]''
The '''L98''' is a slightly modified version of the L76. Since Holden does not use displacement on demand, some redundant hardware was removed from the L76. Power increased to 362&nbsp;hp (270&nbsp;kW) at 5700&nbsp;rpm and 391&nbsp;ft·lbf (530&nbsp;Nm) at 4400&nbsp;rpm.


Applications:
Most LD8 Northstars are rated at {{Convert|275|hp|kW|0|abbr=on}} and {{Auto lbft|300}}.
* 2006 (MY06) Holden VZ SS Thunder Ute
* 2006-2007 [[Holden VE Commodore]]
* 2006-2007 [[Holden WM Statesman]] / [[Holden WM Caprice]]
* 2007-2008 [[Chevrolet Lumina]] SS
* 2007-2008 [[Chevrolet Caprice]] SS


===LS3===
{| class=wikitable
[[Image:GM LS3 Engine.jpg|250px|thumb|right|GM LS3 Engine in a 2008 [[Chevrolet Corvette]]]]
!Year
!Model
!Power
!Torque
|-
|1994||[[Cadillac Eldorado]]||{{Convert|270|hp|kW|0|abbr=on}}||{{Auto lbft|300}}
|-
|1995–2001||[[Cadillac Eldorado]]||{{Convert|275|hp|kW|0|abbr=on}} at 5750&nbsp;rpm||{{Auto lbft|300}}
|-
|2002||[[Cadillac Eldorado]]||{{Convert|275|hp|kW|0|abbr=on}} at 5600&nbsp;rpm||{{Auto lbft|300}} at 4000&nbsp;rpm
|-
|1994||[[Cadillac Seville]] ''SLS''||{{Convert|270|hp|kW|0|abbr=on}}||{{Auto lbft|300}}
|-
|1995–2001||[[Cadillac Seville]] ''SLS''||{{Convert|275|hp|kW|0|abbr=on}}||{{Auto lbft|300}}
|-
|2002–2004||[[Cadillac Seville]] ''SLS''||{{Convert|275|hp|kW|0|abbr=on}}||{{Auto lbft|300}}
|-
|1994||[[Cadillac DeVille]] ''Concours''||{{Convert|270|hp|kW|0|abbr=on}}||{{Auto lbft|300}}
|-
|1995||[[Cadillac DeVille]] ''Concours''||{{Convert|275|hp|kW|0|abbr=on}} at 5750&nbsp;rpm||{{Auto lbft|300}}
|-
|1996–2001||[[Cadillac DeVille]]||{{Convert|275|hp|kW|0|abbr=on}} at 5750&nbsp;rpm||{{Auto lbft|300}}
|-
|2002–2005||[[Cadillac DeVille]]||{{Convert|275|hp|kW|0|abbr=on}} at 5600&nbsp;rpm||{{Auto lbft|300}} at 4000&nbsp;rpm
|-
|2006–||[[Cadillac DTS]]||{{Convert|275|hp|kW|0|abbr=on}} at 6000&nbsp;rpm||{{Auto lbft|295}} at 4400&nbsp;rpm
|-
|2004–2005||[[Pontiac Bonneville]] ''GXP''||{{Convert|275|hp|kW|0|abbr=on}} at 5600&nbsp;rpm||{{Auto lbft|300}} at 4000&nbsp;rpm
|-
|2006–||[[Buick Lucerne]] ''CXS''||{{Convert|275|hp|kW|0|abbr=on}} at 6000&nbsp;rpm||{{Auto lbft|295}} at 4400&nbsp;rpm
|}


:''LS3 can also refer to a 402&nbsp;CID [[Chevrolet Big-Block engine]] of the 1970s''
=== LH2 ===
The Northstar was designed originally for transverse [[front-wheel drive]] applications. It was modified substantially in 2004 for [[longitudinal engine|longitudinal]] [[rear-wheel drive|rear-]] and [[all-wheel drive]] use in the [[Cadillac SRX|SRX]] and [[Cadillac XLR|XLR]], as well as receiving variable valve timing. The RWD ('''LH2''') Northstar produces {{Convert|320|hp|kW|0|abbr=on}} and {{Auto lbft|315}}. An increased compression ratio of 10.5:1 enables most of the increase in power from the L37 and LD8 Northstars.
{| class=wikitable
!Year
!Model
!Power
!Torque
|-
|2004–||[[Cadillac SRX]]||{{Convert|320|hp|kW|0|abbr=on}} @ 6400&nbsp;rpm||{{Auto lbft|315}} @ 4400&nbsp;rpm
|-
|2004–||[[Cadillac XLR]]||{{Convert|320|hp|kW|0|abbr=on}} @ 6400&nbsp;rpm||{{Auto lbft|310}} @ 4400&nbsp;rpm
|-
|2004–||[[Cadillac STS]]||{{Convert|320|hp|kW|0|abbr=on}} @ 6400&nbsp;rpm||{{Auto lbft|315}} @ 4400&nbsp;rpm
|}


The '''LS3''' was introduced as the Corvette's new base engine for the 2008 model year. It produces {{convert|430|hp|kW|abbr=on}} at 5900&nbsp;rpm and {{convert|424|lbf.ft|N.m|abbr=on}} at 4600&nbsp;rpm without the optional Corvette exhaust and is SAE certified. The block is an updated version of the LS2 casting featuring a larger bore of {{convert|4.06|in|mm|abbr=on}} creating a displacement of 6.2&nbsp;L ({{convert|6162|cc|CID|disp=s|abbr=on}}). It also features higher flowing cylinder heads sourced from the [[GM Vortec engine#6200|L92]], a more aggressive camshaft with 0.551" lift, a revised valvetrain with {{convert|6|mm|in|abbr=on}} offset intake rocker arms, a high-flow intake manifold and 47&nbsp;lb/hr fuel injectors from the LS7 engine.
===Supercharged LC3===
A {{Auto Lrev|266}} [[supercharged]] Northstar is used in the 2006 [[Cadillac STS|Cadillac STS-V]] and [[Cadillac XLR|Cadillac XLR-V]]. The bore was reduced for increased strength and improved head gasket sealing. [[Variable valve timing]] is used on both the intake and exhaust sides. The STS-V engine produces {{Convert|469|hp|kW|0|abbr=on}} at 6400 RPM and {{Auto lbft|439}} at 3900&nbsp;rpm with 9:1 compression and the XLR-V engine produces {{Convert|443|hp|kW|0|abbr=on}} at 6400 RPM and {{Auto lbft|414}} at 3900&nbsp;rpm.


The L76/L92/LS3 cylinder heads use {{convert|2.165|in|mm|abbr=on}} intake valves, and {{convert|1.59|in|mm|abbr=on}} exhaust valves. Improved manufacturing efficiency makes these heads cheaper than the outgoing LS6 heads, and severely undercuts aftermarket heads. The large valves, however, limit maximum rpm - 6000 in the L76 (with AFM), and 6600 in the LS3 (with hollow stem valves).
{| class=wikitable
!Year
!Model
!Power
!Torque
|-
|2006–||[[Cadillac STS|Cadillac STS-V]]||{{Convert|469|hp|kW|0|abbr=on}} at 6400&nbsp;rpm||{{Auto lbft|439}} at 3900&nbsp;rpm
|-
|2006–||[[Cadillac XLR|Cadillac XLR-V]]||{{Convert|443|hp|kW|0|abbr=on}} at 6400&nbsp;rpm||{{Auto lbft|414}} at 3900&nbsp;rpm
|}


In addition to the above, a dual mode exhaust package with a bypass on acceleration is available. The dual-mode exhaust uses vacuum-actuated outlet valves, which control engine noise during low-load operation, but open for maximum performance during high-load operation. The system is similar to the C6 Z06, but uses a {{convert|2.5|in|mm|abbr=on}} diameter exhaust compared to the Z06's {{convert|3|in|mm|abbr=on}}. Power is boosted to {{convert|436|hp|kW|abbr=on}} and {{convert|428|lbf.ft|N.m|abbr=on}} with this option.  
== L47 ==
[[Image:4.0 L V8 Aurora.jpg|200px|thumb|A ''L47'' inside an [[Oldsmobile Aurora|Aurora's]] engine bay]]The '''L47 Aurora engine''' was a special [[V8]] designed for the [[Oldsmobile Aurora]], based on the Northstar engine. It is a [[DOHC]] {{auto cc|3995}} V8 which produced 250&nbsp;[[horsepower]] (186&nbsp;kW) and 260&nbsp;ft·lbf (353&nbsp;N·m) of [[torque]]. The bore is 87&nbsp;mm and the stroke is 84&nbsp;mm. The L47 has a 10.3:1 compression ratio and uses premium fuel.


From April 2008, Australian performance car manufacturer, HSV, adopted the LS3 as its standard V8 throughout the range, replacing the LS2. The LS3 received modifications for its application to HSV's models, producing {{convert|425|hp|kW|abbr=on}}. Power and torque was restricted to protect the drivetrain currently used in the E-Series sedans.
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 and simplified [[Rochester Products Division|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 prevents the starter from engaging if the quiet L47 is already running.


Applications:
A highly modified version of this engine was used by General Motors racing division initially for [[Indy Racing League]] competition starting in 1995, then was later used in the [[Cadillac Northstar LMP]] program in 2000.  Both engines retained the 4.0&nbsp;L capacity, but the Northstar LMP version was twin-turbocharged.
* April 2008-present [[Holden Special Vehicles]] (all V8 models)
* 2008-present [[Chevrolet Corvette C6|Chevrolet Corvette]]
* 2009 Pontiac G8 GXP (source: Pontiac web site, "Upcoming Vehicles," 3-16-2008)
* June 2008-present [[Vauxhall VXR8]]
* 2010 [[Fifth-generation Chevrolet Camaro|Chevrolet Camaro]]
* The show [[Top Gear]] used the LS3 to power a blender.<ref name='Top Gear Engine-Powered Blender'>{{cite web | title=Top Gear Builds Corvette Engine-Powered Blender| url=http://jalopnik.com/5090926/top-gear-builds-corvette-engine+powered-blender| accessdate = 2008-11-17}}</ref>


===L99===
The Aurora was also used in the [[Shelby Series 1]] car.
:''For the {{Convert|4.3|L|CID|abbr=on}} Generation II engine of the same RPO, see [[GM_LT_engine#L99_.284.3L.29|GM LT Engine]]''


The '''L99''' is derived from the LS3 with reduced output but adds [[Active Fuel Management]] (displacement on demand), which allows it to run on only four cylinders during light load conditions.<ref>[http://paultan.org/archives/2008/07/23/2010-chevrolet-camaro-details-and-hi-res-photos/ 2010 Chevrolet Camaro Details and Hi-Res Photos]</ref> Power is {{Convert|400|hp|0|abbr=on}} and {{Convert|395|ft.lbf|0|abbr=on}} of torque.<ref>{{cite web | title=2010 Chevrolet Camaro First Look | date = 2008-07-18 | url = http://www.edmunds.com/insideline/do/Features/articleId=129446 | accessdate = 2008-07-21}}</ref><ref>{{cite web | title=2010 Chevy Camaro - Official Details and Images | date = 2008-07-21 | url = http://www.autoblog.com/2008/07/21/2010-chevy-camaro-official-details-and-images/ | accessdate = 2008-07-21}}</ref>
The Aurora engine was introduced in 1994 for the 1995 model year, and [[General Motors Corporation|General Motors]] has not used this engine since the demise of the [[marque]] in 2004.


Applications:
== LX5 ==
* 2010 [[Fifth-generation Chevrolet Camaro|Chevrolet-Camaro]]
[[Image:3.5L V6 Shortstar.jpg|200px|thumb|A "''Shortstar''" LX5 inside an [[Oldsmobile Intrigue|Intrigue's]] engine bay]]
The '''LX5''' [[V6]] is a [[DOHC]] engine from [[Oldsmobile]], introduced in 1999 with the [[Oldsmobile Intrigue]]. 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 [[GM L47 engine|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'''.


===LS4===
It is not a simple cut-down V8. Although it has a 90° vee-angle like the Northstar and Aurora, the engine block was engineered from scratch, so bore centers are different. It has chain-driven [[dual overhead cam]]s and 4 valves per cylinder, but is an even-firing design with a split-pin crankshaft similar to the modern [[GM 3800 engine]]s. The LX5 displaced {{auto cc|3473}} and produced 215&nbsp;hp (160&nbsp;kW) and 230&nbsp;ft·lbf (312&nbsp;N·m). Bore is {{convert|89.5|mm|in|abbr=on}} and stroke is {{convert|92|mm|in|abbr=on}}. Compression ratio is 9.3:1.
[[Image:2006 Chevrolet Impala SS LS4 engine.jpg|right|thumb|250px|5.3&nbsp;L LS4 V8 in a 2006 [[Chevrolet Impala]] SS]]


:''LS4 can also refer to a 454&nbsp;CID [[Chevrolet Big-Block engine]] of the 1970s''
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&nbsp;L to 3.7&nbsp;L, but only the LX5 was ever produced. It was entirely different from any other V6 in the GM inventory, and as with the Aurora V8, production stopped with the demise of [[Oldsmobile]].


The '''LS4''' is a smaller 5.3&nbsp;L ({{convert|5328|cc|CID|disp=s|abbr=on}}) version of the Generation IV block. Though it has the same displacement as the [[GM Vortec engine#5300|Vortec 5300 LH6]], it differs in that it has an aluminum block rather than an iron one and it uses the same cylinder head as the Generation III LS6 engine.
This engine was used in the following:
* 1999-2002 [[Oldsmobile Intrigue]]
* 2001-2002 [[Oldsmobile Aurora]]


This engine is adapted for [[transverse engine|transverse]] [[front-wheel drive]] applications.  According to GM, "The crankshaft is shortened 13 mm – 3 mm at the flywheel end and 10 mm at the accessory drive end – to reduce the length of the engine compared to the 6.0L. All accessories are driven by a single serpentine belt to save space. The water pump is mounted remotely with an elongated pump manifold that connects it to the coolant passages. Revised oil pan baffles, or windage trays, are incorporated into the LS4 to ensure that the oil sump stays loaded during high-g cornering." <ref>{{Citation
The 3.5L LX5 was on the [[Ward's 10 Best Engines]] list for 1999 and 2000.
| title = LS4 Overview - GM Powertrain
| url = http://media.gm.com/us/powertrain/en/product_services/2008/Whats%20New/Gen%20IV/Gen%20IV%20Car/08_LS4.doc
}}</ref> [[Active Fuel Managemment]] is also used. Output of this version is 303&nbsp;hp (226&nbsp;kW)/300 hp on LaCrosse Super and 323&nbsp;ft·lbf (438&nbsp;N·m).


Applications:
== References ==
* 2006-2009 [[Chevrolet Impala]] SS
* {{cite journal|title=Technical Highlights|journal=[[Car and Driver]]|pages=115|issue=October 1993}}
* 2006-2007 [[Chevrolet Monte Carlo]] SS
* {{cite journal|title=Northstar is heart of Allante re-do for '93 - V-8 engine, General Motors' Cadillac Motor Car Div.'s new model roadster|journal=[[Ward's Auto World]]|author=Joel D. Pietrangelo|issue=February 1992}}
* 2005-2008 [[Pontiac Grand Prix]] GXP
* 2008 [[Buick LaCrosse]] Super


===LS7===
== See also ==
[[Image:2006 Chevrolet Corvette Z06 LS7 engine.jpg|right|thumb|250px|7.0&nbsp;L LS7 engine in a 2006 [[Chevrolet Corvette]] Z06]]
* [[GM High Feature engine]]
* [[Cadillac V8 engine]]
* [[List of GM engines]]


:''LS7 can also refer to a 454&nbsp;CID [[Chevrolet Big-Block engine]] of the 1970s''
== External links ==
* [http://www.autospeed.com/cms/A_1569/article.html Technical article from AutoSpeed]
* [http://waw.wardsauto.com/ar/auto_general_motors_corp_3 Ward's article]


The '''LS7''' is a 7.0&nbsp;L ({{convert|7011|cc|CID|disp=s|abbr=on}}) engine, based on the Gen IV architecture. The block is changed, with sleeved pistons and a larger 4.125&nbsp;in (104.9&nbsp;mm) bore and longer 4.00&nbsp;in (101.6&nbsp;mm) stroke than the LS2. The small-block's 4.4&nbsp;in (111.8&nbsp;mm) bore spacing is retained, requiring pressed-in cylinder liners. The crankshaft and main bearing caps are [[forged]] steel for durability, the connecting rods are forged titanium, and the pistons are [[Hypereutectic piston|hypereutectic]].  The two-valve arrangement is retained, though the titanium intake valves by [[Del West]] have grown to 2.20&nbsp;in (55.9&nbsp;mm) and sodium-filled exhaust valves are up to 1.61&nbsp;in (40.9&nbsp;mm).
{{DEFAULTSORT:Northstar}}
 
[[Category:Cadillac engines]]
Peak output is 505&nbsp;hp (377&nbsp;kW) at 6300&nbsp;rpm and 470&nbsp;ft·lbf (637&nbsp;N·m) at 4800&nbsp;rpm with a 7000&nbsp;rpm [[redline]] setting a new record for a production overhead valve pushrod engine.{{Fact|date=December 2007}}  During GM's reliability testing of this engine in its prototype phase, the LS7 was remarked to have been repeatedly tested to be 8000 rpm capable, although power was not made at that rpm level, due to the constraints of the camshaft's profile and the intake manifold ability to flow required air at that engine speed.
[[Category:GM engines]]
 
The LS7 is hand-built by the [[General Motors Performance Build Center]] in [[Wixom, Michigan]]. Most of these engines are installed in the Z06, but some are also sold to individuals by GM as a [[crate engine]].
 
After an extensive engineering process over several years, Holden Special Vehicles fitted the LS7 to a special edition model, the [[HSV W427|W427]]. The HSV-tuned engine produces 375kW (503hp) and 640Nm, making it the most powerful car ever built in Australia. The W427 was unveiled at the [[Melbourne International Motor Show]] on the 29th February, 2008<ref>[http://www.smh.com.au/news/national/revealed-our-fastest-most-expensive-road-car/2008/02/28/1203788544765.html Revealed: our fastest, most expensive road car - National - smh.com.au<!-- Bot generated title -->]</ref> and went on sale in August 2008.
 
Applications:
* 2006-2008 [[Chevrolet Corvette#C6 Z06|Chevrolet Corvette Z06]]
* 2008 [[HSV W427]]
 
===LS7.R===
The '''LS7.R''' engine is a variation of the LS7 used in the highly successful [[Chevrolet Corvette C6.R|C6.R]] [[American Le Mans Series]] racecar.  It was crowned as Global Motorsport Engine of the Year by a jury of 50 race engine engineers on the [[Professional Motorsport World Expo]] 2006 in [[Cologne]], [[Germany]].
 
===LSX===
At the 2006 [[SEMA]] show, GM Performance Parts introduced the LSX engine, an all-new cast-iron racing block based on the LS7 engine. It was designed with help from drag racing legend [[Warren Johnson]].  It offers displacements ranging from 364 cubic inches to 511 cubic inches (4.25" Bore x 4.5" Stroke) and is capable of withstanding 2500 bhp.  This block incorporates two extra rows of head-bolt holes per bank for increased clamping capacity. The six bolt steel main caps are the same ones used on the LS7 engine. The engine debuted at the auto show in a customized 1969 Camaro owned by [[Reggie Jackson]]. The LSX will be available starting the second quarter of 2007, set to be available in authorized dealerships and retailers on March 31, 2007.<ref name='Edmunds Reggie Jackson article'>{{cite web | first= Ed| last= Hellwig| title= 2006 SEMA Show - Reggie Jackson Camaro| date= 2006-10| url= http://www.edmunds.com/insideline/do/AutoshowArticles/articleId=117396| work = Edmunds Inside Line| accessdate = 2007-08-30}}</ref>
 
===LS9===
The '''LS9''' is a 6.2&nbsp;L ({{convert|6162|cc|CID|disp=s|abbr=on}}) supercharged engine, based on the LS3; the LS7 block was not used due to the higher cylinder pressures created by the supercharger requiring the thicker cylinder walls of the LS3. Cylinder dimensions are now 4.06&nbsp;in (103.25&nbsp;mm) bore with a 3.62&nbsp;in (92&nbsp;mm) stroke. It is equipped with an Eaton four-lobe [[Roots type supercharger]]. Power output is {{Convert|638|hp|kW|0|abbr=on}} at 6500&nbsp;rpm and {{auto lbft|604}} of torque at 3800&nbsp;rpm.
 
Applications:
* 2009 [[Chevrolet Corvette C6 ZR1|Chevrolet Corvette ZR1]]
 
===LSA=== 
The supercharged 6.2&nbsp;L '''LSA''' is similar to the LS9 and scheduled to debut in the 2009 Cadillac CTS-V. The LSA has been SAE certified at {{convert|556|hp|kW|abbr=on}} @ 6100rpm  and {{convert|551|lbft|Nm|abbr=on}} of torque @ 3800rpm. GM labels it "the most powerful ever offered in Cadillac’s nearly 106-year history". The LSA features a smaller 1.9&nbsp;L capacity supercharger rather than the 2.3&nbsp;L variant of the LS9. Other differences include a slightly lower 9.0:1 compression ratio, single unit heat exchanger and cast pistons.
 
Applications:
* 2009 [[Cadillac CTS V-Series]]
 
==Vortec engines==
{{for2|information on GM Vortec engines|[[GM Vortec engine]]}}
 
Versions of both the Generation III and Generation IV V8 have also been used in trucks and SUVs.  These are usually branded as GM Vortec engines.
 
==Problems==
 
In the early production run of the LS-series engine, some engines encountered abnormal amounts of 'piston slap' - a problem caused by too much clearance between the cylinder bore and the piston. <ref name='Piston Slap'>{{cite web | title= GM Piston Slap| url= http://www.pistonslap.com/index.html| accessdate = 2007-08-30}}</ref> 'Piston Slap' sometimes sounds more like a knock or the sound of a [[diesel engine]] running, it is also typically worse when the engine is cold and lessens as the engine reaches operating temperature.  The noise of 'Piston Slap' often is louder when listening for it below the [[oil pan]].
 
==See also==
* [[GM Small-Block engine]] - Generation I
* [[GM LT engine]] - Generation II
* [[Chevrolet Corvette]]
* [[Holden Commodore]]
* [[Holden Special Vehicles]]
 
==References==
<div class='references-small'>
<references/>
</div>
 
==External links==
* [http://www.autospeed.com/cms/A_2054/article.html LS1 article at AutoSpeed] 
* [http://www.autospeed.com/cms/A_2062/article.html LS2 article at AutoSpeed]
* [http://ls1tech.com/forums/ LS1Tech Forums]
 
[[Category:GM engines|LS]]
[[it:GM Serie LS]]

Revision as of 00:47, 3 February 2009

GM Premium V
ManufacturerGeneral Motors
Also calledCadillac Northstar
Production1991–
PredecessorCadillac HT V8
LQ1 V6

The Premium V family of automobile engines is General Motors' modern 90° v engine architecture. The family is most associated with Cadillac's Northstar V8, but the family has also seen use at Oldsmobile (as the Aurora L47 V8 and "Shortstar" LX5). The Oldsmobile variants are no longer in production, but the Northstar family has expanded with new longitudinal and 4.4 L supercharged versions. The Northstar name is now used outside Cadillac as well, with the Pontiac and Buick versions now carrying that moniker. Alfa Romeo is rumored to be another future user of the Premium V in the US-market Kamal.

Development and features

The Premium V design was initiated as a response to the advanced dual overhead cam V8 engines introduced by European and Japanese competitors of Cadillac in the late 1980s. At that time, Cadillac was using the aluminum HT Overhead Valve (OHV) V8 which had been pushed hastily into production after the failure of the V8-6-4 of 1981.

Cadillac was developing new models like the Allanté and updated Eldorado and Seville STS which they hoped would compete against the best from BMW, Mercedes-Benz, Lexus, and Infiniti. They developed a laundry list of items that must be included in these new models, including sophisticated steering, braking, and suspension technologies, which became known as the Northstar System. One key element was a high-tech V8 engine with all of the features and performance of the competitors' offerings.

The "Northstar" V8, as it was then known, was an evolution of the Lotus-designed Chevrolet LT5 all-aluminum DOHC 32-valve V8 used in the Corvette ZR-1. Archrival Ford Motor Company was developing a similar engine at that time as well, and Ford's Modular engine would precede the Northstar into production with its introduction on the 1991 Lincoln Town Car. Both continue in production at 4.6 L of displacement.

Capable of producing 300 hp (224 kW), the Northstar featured a unique die-cast aluminum 90° V8 block with 102 mm (4 in) bore spacing split into unitary upper and lower halves. The lower crankcase assembly supported the crankshaft without conventional main bearing caps. An oil manifold plate with an integrated silicon gasket forms the oil gallery under this. A typical oil change used 8.5 U.S. quarts (7.1 imp qt).

Cast-iron cylinder liners were specified and the forged aluminum pistons included valve clearance, making Northstar a non-interference engine, with bronze pin bushings and free-floating piston pins used.

The one-piece cast aluminum cylinder heads extend around the "maintenance-free" cam-drive chain case. Direct-acting hydraulic valves are used 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 were fabricated from magnesium for light weight.

Eight thermoplastic tubes were used in the induction system, leading to sequential fuel injection. Direct ignition was a novelty for the time, with an electronic system adjusting spark and fuel injection timing as well as the shift points for the new 4T80-E transmission.

One notable feature, advertised at the time, was the fail-safe cooling mode which allowed the engine to continue running for a limited time without any coolant at all. It alternated banks of cylinders, basically "air cooling" the inside of the cylinders, to maintain cool temperatures, allowing a Northstar-equipped car to be driven with no coolant for about 100 mi (161 km) with no damage.

Another unusual feature of some Northstar-equipped cars is a liquid-cooled alternator used on Cadillac's Seville, DeVille, and Eldorado. The liquid-cooling helped prolong the life of the alternator in these electronic-laden models, though GM reverted to a traditional air-cooled setup for 2001 to eliminate potential leak points and extraneous tubing.

All engines of this family share the same Northstar bellhousing pattern.

Later developments included variable valve timing, which can vary intake by up to 40° and the exhaust by up to 50°. This system was devised for the longitudinal LH2 version, and has not, to date, been used on the transverse front wheel drive engines due to packaging considerations.


Northstar

The engine was introduced in mid-1992 in the 1993 Cadillac Allanté and continues to be used in most Cadillac models. The original Northstar Allanté also introduced the Northstar System which included traction control, adaptive suspension, and antilock brakes. Early Northstar had no knock sensors, and required premium grade gasoline to run safely.

The Northstar was sold exclusively by Cadillac for over a decade before being introduced in the 2004 Pontiac Bonneville and 2006 Buick Lucerne. However, the 4.0L L47 V8 variant was used in the Oldsmobile Aurora and the 3.5L LX5 V6 in the Oldsmobile Intrigue. The engine received a forged steel crankshaft in 2003. Cadillac had planned to introduce a V12 Northstar this decade, likely for use in the Escalade, but economics and new CAFE standards have killed this idea.

Most Northstar engines produce 275 hp (205 kW) to 315 hp (235 kW). The engines were revised for 2000 with coil-on-plug ignition and roller follower valvegear for improved fuel economy and reduced emissions. Though power output did not change, this update eliminated the need for premium fuel.

All but the supercharged Northstar displace 4.6 L (279 cu in) with a 93 mm (3.7 in) bore and 84 mm (3.3 in) stroke. For better head gasket sealing between cylinders, the supercharged version is de-bored to 91 mm (3.6 in) for a total displacement of 4.4 L (266 cu in) . The block is said[who?] 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 list for 1995, 1996, and 1997.

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 has been used on all high-output transverse Northstars, even as the exact engine specifications evolved. Compression ratio for the L37 is 10:1, shared with the LD8.

The original L37 was specified at 290 hp (216 kW), but 1993 production examples were rated at 295 hp (220 kW). The engine topped out at 300 hp (224 kW) from 1996 through 2004 on the STS, DTS and ETC models, making these some of the most powerful domestic front wheel drive cars ever built, the most powerful title still belonging to the 1970 Cadillac Eldorado 500 cu in (8.2 L) with 400 hp (298 kW) (although the latter's rating is in the older SAE gross horsepower system, figured without accessories or muffler, where the current engine outputs are as-installed, net ratings). For 2005 the high output Northstar became Northstar NHP, and was downrated to 290 horsepower (220 kW) under the new SAE certified horsepower rating system. In 2006, the updated DTS "Performance Package" model got a slight bump to 292 hp (218 kW).

Vehicles using the L37 include:

Year Model Power Torque
1993 Cadillac Allanté 295 hp (220 kW) 290 lb·ft (393 N·m)
1993-1994 Cadillac Eldorado ETC 295 hp (220 kW) 290 lb·ft (393 N·m)
1995–2002 Cadillac Eldorado ETC 300 hp (224 kW) @ 6000 rpm 295 lb·ft (400 N·m) @ 4400 rpm
1993 Cadillac Seville STS 295 hp (220 kW) 290 lb·ft (393 N·m)
1994–2004 Cadillac Seville STS 300 hp (224 kW) @ 6000 rpm 295 lb·ft (400 N·m) @ 4400 rpm
1996–2004 Cadillac DeVille Concours/DTS 300 hp (224 kW) @ 6000 rpm 295 lb·ft (400 N·m) @ 4400 RPM
2005 Cadillac DeVille DTS 290 hp (216 kW) @ 5600 rpm 285 lb·ft (386 N·m) @ 4400 rpm
2006– Cadillac DTS Performance 292 hp (218 kW) @ 6300 rpm 288 lb·ft (390 N·m) @ 4500 rpm
2008- Buick Lucerne Super 292 hp (218 kW) @ 6300 rpm 288 lb·ft (390 N·m) @ 4500 rpm

LD8

The LD8 (VIN "Y") is a transverse V8 for front-wheel drive cars. Introduced in 1994, it is designed to provide more torque than the high-revving L37. The LD8 code has been used on all torque-tuned transverse Northstars, even as the exact engine specifications evolved. Compression ratio is 10:1.

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 275 hp (205 kW) and 300 lb·ft (407 N·m).

Year Model Power Torque
1994 Cadillac Eldorado 270 hp (201 kW) 300 lb·ft (407 N·m)
1995–2001 Cadillac Eldorado 275 hp (205 kW) at 5750 rpm 300 lb·ft (407 N·m)
2002 Cadillac Eldorado 275 hp (205 kW) at 5600 rpm 300 lb·ft (407 N·m) at 4000 rpm
1994 Cadillac Seville SLS 270 hp (201 kW) 300 lb·ft (407 N·m)
1995–2001 Cadillac Seville SLS 275 hp (205 kW) 300 lb·ft (407 N·m)
2002–2004 Cadillac Seville SLS 275 hp (205 kW) 300 lb·ft (407 N·m)
1994 Cadillac DeVille Concours 270 hp (201 kW) 300 lb·ft (407 N·m)
1995 Cadillac DeVille Concours 275 hp (205 kW) at 5750 rpm 300 lb·ft (407 N·m)
1996–2001 Cadillac DeVille 275 hp (205 kW) at 5750 rpm 300 lb·ft (407 N·m)
2002–2005 Cadillac DeVille 275 hp (205 kW) at 5600 rpm 300 lb·ft (407 N·m) at 4000 rpm
2006– Cadillac DTS 275 hp (205 kW) at 6000 rpm 295 lb·ft (400 N·m) at 4400 rpm
2004–2005 Pontiac Bonneville GXP 275 hp (205 kW) at 5600 rpm 300 lb·ft (407 N·m) at 4000 rpm
2006– Buick Lucerne CXS 275 hp (205 kW) at 6000 rpm 295 lb·ft (400 N·m) at 4400 rpm

LH2

The Northstar was designed originally for transverse front-wheel drive applications. It was modified substantially in 2004 for longitudinal rear- and all-wheel drive use in the SRX and XLR, as well as receiving variable valve timing. The RWD (LH2) Northstar produces 320 hp (239 kW) and 315 lb·ft (427 N·m). An increased compression ratio of 10.5:1 enables most of the increase in power from the L37 and LD8 Northstars.

Year Model Power Torque
2004– Cadillac SRX 320 hp (239 kW) @ 6400 rpm 315 lb·ft (427 N·m) @ 4400 rpm
2004– Cadillac XLR 320 hp (239 kW) @ 6400 rpm 310 lb·ft (420 N·m) @ 4400 rpm
2004– Cadillac STS 320 hp (239 kW) @ 6400 rpm 315 lb·ft (427 N·m) @ 4400 rpm

Supercharged LC3

A 4.4 L (266 cu in) supercharged Northstar is used in the 2006 Cadillac STS-V and Cadillac XLR-V. The bore was reduced for increased strength and improved head gasket sealing. Variable valve timing is used on both the intake and exhaust sides. The STS-V engine produces 469 hp (350 kW) at 6400 RPM and 439 lb·ft (595 N·m) at 3900 rpm with 9:1 compression and the XLR-V engine produces 443 hp (330 kW) at 6400 RPM and 414 lb·ft (561 N·m) at 3900 rpm.

Year Model Power Torque
2006– Cadillac STS-V 469 hp (350 kW) at 6400 rpm 439 lb·ft (595 N·m) at 3900 rpm
2006– Cadillac XLR-V 443 hp (330 kW) at 6400 rpm 414 lb·ft (561 N·m) at 3900 rpm

L47

A L47 inside an Aurora's engine bay

The L47 Aurora engine was a special V8 designed for the Oldsmobile Aurora, based on the Northstar engine. It is a DOHC 4 L (3995 cc, 244 cu in) V8 which produced 250 horsepower (186 kW) and 260 ft·lbf (353 N·m) of torque. The bore is 87 mm and the stroke is 84 mm. The L47 has a 10.3:1 compression ratio and uses 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 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 prevents the starter from engaging if the quiet L47 is already running.

A highly modified version of this engine was used by General Motors racing division initially for Indy Racing League competition starting in 1995, then was later used in the Cadillac Northstar LMP program in 2000. Both engines retained the 4.0 L capacity, but the Northstar LMP version was twin-turbocharged.

The Aurora was also used in the Shelby Series 1 car.

The Aurora engine was introduced in 1994 for the 1995 model year, and General Motors has not used this engine since the demise of the marque in 2004.

LX5

A "Shortstar" LX5 inside an Intrigue's engine bay

The LX5 V6 is a DOHC engine from Oldsmobile, introduced in 1999 with the Oldsmobile Intrigue. 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.

It is not a simple cut-down V8. Although it has a 90° vee-angle like the Northstar and Aurora, the engine block was engineered from scratch, so bore centers are different. It has chain-driven dual overhead cams and 4 valves per cylinder, but is an even-firing design with a split-pin crankshaft similar to the modern GM 3800 engines. The LX5 displaced 3.5 L (3473 cc, 212 cu in) and produced 215 hp (160 kW) and 230 ft·lbf (312 N·m). Bore is 89.5 mm (3.52 in) and stroke is 92 mm (3.6 in). 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. It was entirely different from any other V6 in the GM inventory, and as with the Aurora V8, production stopped with the demise of Oldsmobile.

This engine was used in the following:

  • 1999-2002 Oldsmobile Intrigue
  • 2001-2002 Oldsmobile Aurora

The 3.5L LX5 was on the Ward's 10 Best Engines list for 1999 and 2000.

References

  • "Technical Highlights". Car and Driver (October 1993): 115. 
  • Joel D. Pietrangelo. "Northstar is heart of Allante re-do for '93 - V-8 engine, General Motors' Cadillac Motor Car Div.'s new model roadster". Ward's Auto World (February 1992). 

See also

External links

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