The LY6 engine is a 6.0L Gen. 4 small block engine used in GM trucks and SUVs between 2007 and 2010. For marketing purposes, it was also known as the Vortec 6000. The engine specs and information listed here is for a stock LY6 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: Looking to upgrade your LY6? Read: LY6 6.0L Engine Upgrade Guide: Expert Advice for LY6 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 guide is specifically about the GM LY6. 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.)

Chevy LY6 Engine Specs

LY6 Performance Specifications

LY6 Engine Ratings
Compression Ratio9.6:1
Horsepower Rating364 hp
Torque Rating383 ft.-lbs.

LY6 Applications

LY6 Applications
VIN 8th DigitYearMakeModel
K2007-10ChevroletSilverado 2500 HD, 3500 HD
K2007-10GMCSierra 2500 HD, 3500 HD
K2007-09ChevroletSuburban 2500
K2007-09GMCYukon XL 2500
K2008-09ChevroletExpress 2500, 3500
K2008-09GMCSavana 2500, 3500

LY6 Engine Block Specs

LY6 Block Specs
Casting Number12576181
MaterialIron
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 in. Bore 2/4 = 2.326 in. Bore 3 = 2.307 in.
Cam-to-Crank Centerline4.914 in.

LY6 Rotating Assembly

LY6 Rotating Assembly Specs
Piston MaterialHypereutectic Cast Aluminum Alloy
Piston StyleDished with valve reliefs
Piston Volume+6.7cc

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 Number
12607475
Connecting Rod Casting Number (Last 4 Digits)3847
Crankshaft MaterialCast Iron
Crankshaft Casting Number
(Last 3 Digits)
216
Crankshaft Main Journal Dia.2.559 in.
Crankshaft Rod Journal Dia.2.100 in.
Reluctor Wheel58X

LY6 Cylinder Heads

LY6 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

LY6 Camshaft Specs

LY6 Camshaft Specs
Duration @ .050 in. (int./exh.)196°/208°
Valve Lift (int./exh.)0.467 in./.479 in.
Lobe Separation Angle116°
Cam Gear Attachment1-Bolt
Cam Gear Poles4x
Active Fuel Management (AFM)No
Variable Valve Timing (VVT)Yes

LY6 Valvetrain

LY6 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 OffsetIntake Rocker
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 LY6 Specs

LY6 Throttle Body, Fuel Injector Specs & More
Intake ManifoldTruck-Style
Throttle Body87mm, 4-bolt
Throttle Control Electronic, Drive-by-Wire
Fuel Injector Part Number 12580681
Fuel Injector Flow29.6 lb./hr. @ 58 psi
Flex Fuel CapableNo
Fuel Injector Length Between O-Rings 1.900 in.
Fuel Injector Connector EV6 / USCAR
PCME38
Crankshaft Reluctor Ring58x
Camshaft Sensor LocationFront mount, 4x on cam
Oil Pan
Deep Rear Sump
Oil PumpStandard Flow
(0.96 c.i. per rev.)

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.

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