The L76—like its LS2 sibling—is a 6.0L, Gen. 4, aluminum small block engine that was used both in GM cars and trucks. The L76 is an adapted version of the LS2, featuring new rectangle port cylinder heads and Active Fuel Management (AFM).
The L76 was available in the Pontiac G8 GT from 2007-09. It was also used in some Australian Holden cars.
(NOTE: Don’t confuse the engine specs here with the L-76 5.4L small block which could be found in the C2 Sting Ray Corvette in 1964.)
The information listed below is for the stock L76 car engine.
Mechanically similar, General Motors’ LS and LS-based Vortec engines wound up on almost every branch of the GM family tree: Chevy, Pontiac, GMC, Cadillac, Buick—heck, even Saab, Hummer, and Isuzu got some LS love.
Since LS and Vortec engines are so common, they’ve become the go-to performance and swap engines of the modern era.
These motors are capable of making a lot of horsepower, and respond well to upgrades like turbos, superchargers, high-flow cylinder heads, intake systems, cams, and nitrous oxide.
[NOTE: The L76 appeared in both cars AND trucks, and there are some differences between the two. To read about the L76 truck engine specifically, check out L76 Truck Engine Specs: Performance, Bore & Stroke, Cylinder Heads, Cam Specs & More.]
The aftermarket is strong for LS swap engines. Crate engines are available, and used motors are often cheaply sourced through junkyards.
Summit Racing has created a series of comprehensive guides for each engine in the LS family, so engine builders and tuners can have a handy reference for their projects.
This guide is specifically about the GM L76 car engine. You can find our other LS engine spec guides and LS-related tech articles here.
(Summit Racing’s Paul Spurlock and Brian Nutter contributed to this article.)
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GM L76 Car Engine Specs
L76 (Car) Performance Specifications
| Engine Ratings | |
|---|---|
| Compression Ratio | 10.4:1 |
| Horsepower Rating | 355 hp |
| Torque Rating | 384 ft./lbs. |
L76 (Car) Applications
| VIN 8th Digit | Year | Make | Model |
|---|---|---|---|
| Y | 2007-09 | Pontiac | G8 GT |
| N/A | 2006 | Holden | Commodore VZ Series II |
| N/A | 2009-10 | Holden | Commodore VE Series I |
| Note: The Australian vehicles use a different format for Vehicle Identification Numbers (VIN). The 8th digit is NOT the engine code in an Australian VIN code. | |||
L76 (Car) Engine Blocks
| L76 (Car) Block Specs | |
|---|---|
| Casting Numbers | 12568952 |
| Material | Aluminum |
| Displacement | 6.0L / 364 c.i.d. |
| Bore Dia. | 4.000 in. |
| Stroke | 3.622 in. |
| Deck Height | 9.240 in. |
| Bore Spacing | 4.400 in. |
| Thrust Bearing Location | #3 Main |
| Main Cap Style | 6-Bolt |
| Main Housing Bore Dia. | 2.751 in. |
| Cam Housing Bore Dia. | Bore 1/5 = 2.346, Bore 2/4 = 2.326, Bore 3 = 2.307 |
| Cam-to-Crank Centerline | 4.914 in. |
L76 (Car) Rotating Assembly
| L76 (Car) Rotating Assembly Specs | |
|---|---|
| Piston Material | Hypereutectic Cast Aluminum Alloy |
| Piston Style | Flat Top |
| Piston Volume | 0cc |
| Wrist Pin Dia. | 0.9431 in. (full floating) |
| Connecting Rod Material | Powdered Metal |
| Connecting Rod Style | I-Beam |
| Connecting Rod Length | 6.098 in. |
| Connecting Rod Housing Bore | 2.225 in. |
| Connecting Rod Bolts | M9 x 1 x 43 |
| Connecting Rod Part Number | 12649190 |
| Crankshaft Material | Cast Iron |
| Crankshaft Part Number | 12588613 |
| Crankshaft Main Journal | 2.559 in. |
| Crankshaft Rod Journal | 2.100 in. |
| Reluctor Wheel | 58x |
L76 (Car) Cylinder Heads
| L76 (Car) Cylinder Head Specs | |
|---|---|
| Casting Numbers | 5364, 823 |
| Material | Aluminum |
| Combustion Chamber Volume | 70cc |
| Intake Port Shape | Rectangle |
| Intake Runner Volume | 257cc |
| Exhaust Port Shape | D-Port |
| Exhaust Runner Volume | 87cc |
| Intake Valve Diameter | 2.165 in. |
| Exhaust Valve Diameter | 1.590 in. |
| Cylinder Head Bolt Style | Torque to Yield (TTY) |
| Cylinder Head Bolt Size | (10) M11 x 2 x 100, (5) M8 x 1.25 x 45 |
L76 (Car) Camshaft
| L76 (Car) Cam Specifications | |
|---|---|
| Camshaft Part Number | 12625439 |
| Duration @ .050 in. (int./exh.) | 196°/208° |
| Valve Lift (int./exh.) | 0.478 in./0.466 in. |
| Lobe Separation | 116° |
| Cam Gear Attachment | 1-Bolt |
| Cam Gear Poles | 4x |
| Active Fuel Management (AFM) | Yes, on the Pontiac G8 GT and the 2009-10 Commodore with an automatic transmission |
| Active Fuel Management (AFM) | No, on the 2006 Commodore and the 2009-10 Commodore with a manual transmission |
| Variable Valve Timing (VVT) | No |
L76 (Car) Valvetrain
| L76 (Car) Valvetrain Specs | |
|---|---|
| Lifter Style | Hydraulic Roller |
| Lifter Link Style | Plastic Lifter Tray |
| Lifter Body Diameter | 0.842 in. |
| Pushrod Length | 7.385 in. |
| Rocker Arm Mounting Style | Pedestal |
| Rocker Arm Style | Die-Cast, Roller Fulcrum |
| Rocker Ratio | 1.7 |
| Rocker Offset | Offset Intake |
| Valve Spring Style | Beehive |
| Valve Spring Color | Natural |
| Valve Angle | 15 Degrees |
| Intake Valve Material | Steel - Solid Stem |
| Intake Valve Dia. | 2.165 in. |
| Exhaust Valve Material | Steel - Solid Stem |
| Exhaust Valve Dia. | 1.590 in. |
Other Key L76 (Car) Specs
| Throttle Body, Fuel Injectors, Oil Pan Specs & More | |
|---|---|
| Intake Manifold | Car-Style |
| Throttle Body | 90mm, 4-bolt |
| Throttle Control | Electronic (Drive-by-Wire) |
| Fuel Injector Part Number | 12576341 |
| Fuel Injector Flow | 42 lb./hr. @ 58 psi |
| Flex Fuel Capable (E-85) | No |
| Fuel Injector Length (between O-Rings) | 1.500 in. |
| Fuel Injector Connector | EV6-USCAR |
| Computer | E38 |
| Crankshaft Reluctor Ring | 58x |
| Camshaft Sensor Location | Front Timing Cover, 4x |
| Oil Pan | Varies By Model |
| Oil Pump | High Volume (1.26 c.i. per rev. @ 33 psi) |
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NOTE: You can find engine specs and detailed engine upgrade advice for every LS and LS-based Vortec truck engine in one place: The Definitive Guide to LS Engine Specs and LS Engine Upgrades.
[…] [Every engine spec you’ll need for an LFA project can be found here: LFA Engine Specs: Performance, Bore & Stroke, Cylinder Heads, Cam Specs & More.] […]
No such thing as a 2007 Pontiac G8. Only the 2008 and 2009 model years exist. Good article otherwise.
I noticed this article did not mention (DOD) displacement on demand. Also I saw other articles advertising 361 h.p. But other than that, I found this info very good.
It said AFM above. Same thing. 361hp was the 08 model
Along with 08, was not the 09.1 still rated at 361?
I was under the impression the hp droped with the 09.5 when the extra cats were added
Pretty sure the drop in hp from 361 to 355 was due to the recalibration for regular unleaded gas. I believe the 08 was tuned for premium gas. GM had to make changes since the gas prices were spiking all over the world in 09 and they had a hard time selling V8 sedans.
[…] [Every engine spec you’ll need for an L76 project can be found here: L76 Car Engine Specs: Performance, Bore & Stroke, Cylinder Heads, Cam Specs & More.] […]
I own one of the Australian Cars with a LS2 – L76 in a HSV VZ 2006 Clubsport HRT Edition No 21 of 50 Made.. hear the Dyno from installing a OTR to a 115mm Intake system that was standard for this Car = 266KW or 357Hp @ 5,500Rpm = 530Nm tongue @ 4,500Rpm, Max Rpm is 8,500 before start of drop off.. It has to be run on min of 95 Unleaded petrol, Average under 10L Per 100Kms in highway & a round 14L per 100Kms in city. it has a M12 6 speed gearbox with a twin plate ceramic clutch.. 0 to 100Kms in 3.2 seconds, 0 to 250Kms in 11.8 seconds but that might be me as with T/C off it takes a couple of seconds to to gather the 3rd gear step @ 170 to 180Kms when max torque kicks in.. Have got 200Mph out of 5th Gear & still what to know what 6th gear will do..
Love to know what would be a good upgrade for it??? looking @ going to a 3″ exhaust for a 2 1/2″ system and playing with the idea of going a Harrop Stealth Supper Charger (HTV2300) putting out 500Kw / @ 5,500Rpm with 8 psi boost.. so i can keep the Throttle response it has with out having to redo cams or heads for better flow.. In the big picture it as still a daily driver for Me… A 175Kw @ 800Rpm takes some getting used to for the normal person..
Pontiac G8 was only available in a 2008 and 2009 year model in the USA. Production for this vehicle began Dec. of 2007 and sales began January 2008. Prior to that it was a Holden Commodore in Australia. Thank you-
Hi,
Good place to purchase camshaft bearings std/oem bore: bore 1/5=2.346, bore 2/4=2.326, bore 3= 2.307. Miles on car right now 110.225, thanks.
Hey Steven, Summit Racing’s got a wide assortment of cam bearings for you.
Hi there, my VE Commodore Wagon 6 litre has AFM and not 823 but stampted 821 heads, did the factory put them on or previous owner, im not sure, everywhere I read I see this car should be 823, seems i’m lucky.
Hi there, my VE Commodore Wagon 6 litre has AFM and not 823 but stamp cast numbered 821 heads, did the factory put them on or previous owner, im not sure, everywhere I read I see this car should be 823, seems i’m lucky.