The LC9 engine is a 5.3L, Gen. 4, aluminum small block engine used in GM trucks and SUVs between 2007-2011.

For marketing purposes, it was also known as the Vortec 5300. The engine specs and information listed here is for a stock LC9 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.

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 LC9 5.3L engine.

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.)

LC9 5.3L Engine Specs

LC9 Performance Specifications

LC9 Engine Ratings
Compression Ratio9.9:1 (2007-09), 9.6:1 (2010-11)
Horsepower Rating302-315 hp
Torque Rating330-338 ft.-lbs.

LC9 Applications

LC9 Applications
VIN 8th DigitYearMakeModel
32007-11ChevroletSilverado 1500
32007-11GMCSierra 1500
32007-11GMCYukon XL

LC9 Engine Block Specs

LC9 Block Specs
Casting Number125771048, 12601900, 12569513, 12568573
Displacement5.3L / 325 c.i.d.
Bore Dia. 3.780 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.

LC9 Rotating Assembly

LC9 Rotating Assembly Specs
Piston MaterialHypereutectic Cast Aluminum Alloy
Piston StyleFlat Top (2007-09), Flat Top with valve reliefs (2010-11)
Piston Volume0cc (2007-09), 3cc (2010-11)
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
Rod Part Number
Connecting Rod Casting Number (last three digits)143
Crankshaft MaterialCast Iron
Crankshaft Part Number
(Last 3 Digits)
Crankshaft Casting Number (last three digits)216
Crankshaft Main Journal Dia.2.559 in.
Crankshaft Rod Journal Dia.2.100 in.
Reluctor Wheel58x

LC9 Cylinder Heads

LC9 Cylinder Head Specs
Casting Numbers799, 243
Combustion Chamber Volume65cc
Intake Port ShapeCathedral
Intake Runner Volume210cc
Exhaust Port ShapeD-Port
Exhaust Runner Volume75cc
Intake Valve Diameter2.000 in.
Exhaust Valve Diameter1.575 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

LC9 Camshaft Specs

Part Number1259320712625436
Duration @ .050 in. (int./exh.)193°/193°196°/201°
Valve Lift (int./exh.)0.482 in./0.482 in.0.481 in./0.481 in.
Lobe Separation Angle116°+2116°+2
Cam Gear Attachment1-Bolt1-Bolt
Cam Gear Poles4x4x
Active Fuel Management (AFM)YesYes
Variable Valve Timing (VVT)NoYes

LC9 Valvetrain

LC9 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 OffsetNone
Valve Spring StyleBeehive
Valve Spring ColorNatural
Valve Angle15 Degrees
Intake Valve MaterialSteel, Solid Stem
Intake Valve Dia.2.000 in.
Exhaust Valve MaterialSteel, Solid Stem
Exhaust Valve Dia.1.575 in.
Timing Chain Guide StyleSpring Loaded Tensioner

LC9 Throttle Body, Fuel Injector Specs & More

Intake ManifoldTruck-StyleTruck-Style
Throttle Body87mm, 4-bolt87mm, 4-bolt
Throttle Control Electronic, Drive-by-Wire Electronic, Drive-by-Wire
Fuel Injector Part Number 1259451212613411
Fuel Injector Flow36 lb./hr. @ 58 psi37.3 lb./hr. @ 58 psi
Flex Fuel CapableYesYes
Fuel Injector Length Between O-Rings 1.890 in.1.730 in.
Fuel Injector Connector EV6 / USCAREV6 / USCAR
Crankshaft Reluctor Ring58x58x
Camshaft Sensor LocationTiming CoverTiming Cover
Oil Pan
Varies by ApplicationVaries by Application
Oil PumpHigh Volume
(1.25 c.i. per rev.)
High Volume
(1.25 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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