The L98 is a 6.0L, Gen. 4, small block aluminum engine used in GM’s Australian Holden vehicles between 2006 and 2010.

The L98 is a slightly modified version of the L76. The main difference is the absence of displacement on demand (DoD) tech. Redundant AFM/DoD hardware was eliminated for the L98, and offered a slight power increase over the L76.

The engine specs and information listed here is for a stock L98 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.

[Looking to upgrade your L98 engine? Check out L98 6.0L Engine Upgrade Guide: Expert Advice for L98 Mods to Maximize Performance.]

The aftermarket is strong, 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 specific guide is for the GM L98 6.0L engine which was exclusive to Holden vehicles in Australia for model years 2006-2010.

You can find more LS engine spec guides and LS-related information here.

(Summit Racing’s Paul Spurlock and Brian Nutter contributed to this article.)

L98 6.0L Engine Specs

L98 Performance Specifications

Engine Ratings
Compression Ratio10.4:1
Horsepower Rating355 hp
Torque Rating384 ft./lbs.

L98 Applications

VIN 8th DigitYearMakeModel
N/A2006HoldenSS Thunder Ute
N/A2006-08HoldenWM - Statesman/Caprice
N/A2006-10HoldenUte (manual only from 2008-10)
N/A2009-10HoldenVE - Commodore (manual only from 2008-10)
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.

L98 Engine Blocks

L98 Block Specs
Casting Numbers12568952
MaterialAluminum
Displacement6.0L / 364 c.i.d.
Bore Dia. 4.000 in.
Stroke3.622 in.
Deck Height9.240 in.
Bore Spacing4.400 in.
Thrust Bearing Location#3 Main
Main Cap Style6-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 Centerline4.914 in.

L98 Rotating Assembly

L98 Rotating Assembly Specs
Piston MaterialHypereutectic Cast Aluminum Alloy
Piston StyleFlat Top
Piston Volume0cc
Wrist Pin Dia.0.9431 in. (full floating)
Connecting Rod MaterialPowdered Metal
Connecting Rod StyleI-Beam
Connecting Rod Length6.098 in.
Connecting Rod Housing Bore2.225 in.
Connecting Rod BoltsM9 x 1 x 43
Connecting Rod Part Number12649190
Crankshaft MaterialCast Iron
Crankshaft Part Number12588613
Crankshaft Main Journal2.559 in.
Crankshaft Rod Journal2.100 in.
Reluctor Wheel58x

L98 Cylinder Heads

L98 Cylinder Head Specs
Casting Numbers5364, 823
MaterialAluminum
Combustion Chamber Volume70cc
Intake Port ShapeRectangle
Intake Runner Volume257cc
Exhaust Port ShapeD-Port
Exhaust Runner Volume87cc
Intake Valve Diameter2.165 in.
Exhaust Valve Diameter1.590 in.
Cylinder Head Bolt StyleTorque to Yield (TTY)
Cylinder Head Bolt Size(10) M11 x 2 x 100, (5) M8 x 1.25 x 45

L98 Camshaft

L98 Cam Specifications
Camshaft Part Number12625439
Duration @ .050 in. (int./exh.)196°/208°
Valve Lift (int./exh.)0.478 in./0.466 in.
Lobe Separation116°
Cam Gear Attachment1-Bolt
Cam Gear Poles4x
Active Fuel Management (AFM)No
Variable Valve Timing (VVT)No

L98 Valvetrain

L98 Valvetrain Specs
Lifter StyleHydraulic Roller
Lifter Link StylePlastic Lifter Tray
Lifter Body Diameter0.842 in.
Pushrod Length7.385 in.
Rocker Arm Mounting StylePedestal
Rocker Arm StyleDie-Cast, Roller Fulcrum
Rocker Ratio1.7
Rocker OffsetOffset Intake
Valve Spring StyleBeehive
Valve Spring ColorNatural
Valve Angle15 Degrees
Intake Valve MaterialSteel - Solid Stem
Intake Valve Dia.2.165 in.
Exhaust Valve MaterialSteel - Solid Stem
Exhaust Valve Dia.1.590 in.

Other Key L98 Specs

Throttle Body, Fuel Injectors, Oil Pan Specs & More
Intake ManifoldCar-Style
Throttle Body90mm, 4-bolt
Throttle ControlElectronic (Drive-by-Wire)
Fuel Injector Part Number12576341
Fuel Injector Flow42 lb./hr. @ 58 psi
Flex Fuel Capable (E-85)No
Fuel Injector Length (between O-Rings)1.500 in.
Fuel Injector ConnectorEV6-USCAR
ComputerE38
Crankshaft Reluctor Ring58x
Camshaft Sensor LocationFront Timing Cover, 4x
Oil PanVaries By Model
Oil PumpHigh Volume (1.26 c.i. per rev. @ 33 psi)

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.