LS Engines

LS7 Engine Specs: Performance, Bore & Stroke, Cylinder Heads, Cam Specs & More

2014-Chevrolet-CamaroZ28-LS7-Engine

The LS7 was found in the 2006-13 Corvette Z06 and 2013 Corvette 427, plus the 2014-15 Camaro Z/28. (Image/GM Corporate Newsroom)

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 LS7 engine.

[Do you have an LS7 engine you want to upgrade? Read: LS7 Engine Upgrade Guide: Expert Advice for LS7 Engine Mods to Maximize Performance.]

You can explore all of our LS engine spec guides and LS tech resources here.

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

Chevy LS7 Engine Specs

The LS7 is a Gen. 4, 7.0L, aluminum small block engine. It was available in GM’s high performance cars between 2006 and 2015.

The LS7 is the largest displacement engine in the LS family. It is unique because it was based on the C5-R Le Mans Corvette racing engine. It was purpose-built for high performance.

Top-End Features

  • Unique high-flow, CNC-ported, square port, cylinder heads and intake manifold
  • Titanium intake valves
  • 1.8 ratio rockers
  • A high lift, long duration camshaft

Bottom-End Features

  • Doweled, billet steel main caps
  • Forged steel crankshaft
  • Titanium connecting rods

Other Performance Features

  • Block machining performed using deck plates to increase accuracy
  • Piston oil-squrters
  • A high-capacity, dry sump oiling system

With these modifications, the LS7 can easily rev to 7,100 rpm. The information listed here is for a stock engine.

LS7 Performance Specifications

Engine Ratings
Compression Ratio11:1
Horsepower Rating505 hp @ 6,300 rpm
Torque Rating470-481 ft./lbs. @ 4,800 rpm
Engine Weight454 lbs. (assembled with clutch, flywheel, balancer, and water pump)

LS7 Applications

VIN 8th DigitYearMakeModel
E2006-13ChevroletCorvette Z06 and
Corvette 427 (2013)
E2014-15ChevroletCamaro Z/28
LS7 Engine Block Specs
Casting Number12598723
Material319-T7 aluminum
Displacement7.0L / 427 c.i.d.
Cylinder LinersPressed in, 5.850 in. long (vs. standard 5.500 in.) to support longer stroke
Bore Dia. 4.125 in.
Stroke4.000 in.
Deck Height9.240 in.
Bore Spacing4.400 in.
Thrust Bearing Location#3 Main
Main Cap StyleDoweled, 6-bolt, billet steel (1141 alloy)
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.
Piston Oil SquirtersYes
Cam-to-Crank Centerline4.914 in.
LS7 Rotating Assembly Specs
Piston MaterialM142 cast aluminum alloy (with anti-friction coating and anodized top ring groove)
Piston StyleFlat top, with valve reliefs
Piston Volume+7cc
Wrist Pin Dia.0.925 in. (Full Floating)
Connecting
Rod Part Numbers
12586258, 126318172, 12661677
Connecting Rod MaterialTitanium
Connecting Rod StyleI-beam, with tapered small end
Connecting Rod Length6.067 in.
Connecting Rod Housing Bore2.225 in.
Connecting Rod BoltsM9 x 1 x 40
Connecting Rod Weight464 grams
Crankshaft MaterialForged 4140 steel (early), Forged 44MNSIVS steel (late)
Crankshaft Part Numbers12611649 (2006-11),
12641692 (2012-15)
Crankshaft Weight56.40-57.65 lbs.
Crankshaft Main Journal Dia.
2.559 in.
Crankshaft Rod Journal Dia.2.100 in.
Reluctor Wheel58X
LS7 Cylinder Head Specs
Casting Number12578452
Material356-T6 Aluminum
Combustion Chamber Volume70cc, CNC-ported
Intake Port ShapeRaised square port, CNC-ported
Intake Runner Volume259cc
Exhaust Port ShapeD-port, CNC-ported
Exhaust Runner Volume86cc
Valve Seat MaterialPMF 28 / Brico 3220
Cylinder Head Bolt StyleTorque to Yield (TTY)
Cylinder Head Bolt Size(10) M11 x 2 x 100, (5) M8 x 1.25 x 45
LS7 Cam Specifications
Camshaft Part Number12638426
Duration @ .050 in. (int./exh.)210°/230°
Valve Lift0.593 in./0.589 in
Lobe Separation120°
Cam Advance-3 degrees
Cam Gear Attachment3-bolt
Cam Gear Poles4X
LS6 Valvetrain Specs
Lifter StyleHydraulic roller (with ceramic check ball for high rpm operation)
Lifter Link StylePlastic Lifter Tray
Lifter Body Diameter0.842 in.
Pushrod Length7.750 in.
Pushrod Dia.0.375 in.
Rocker Arm Mounting StylePedestal
Rocker Arm StyleDie-Cast, Roller Fulcrum
Rocker Ratio1.8
Rocker OffsetIntake only, 9mm total offset
Valve Spring StyleBeehive (LS7 specific)
Valve Spring ColorNatural
Valve Spring Seat Pressure100 lbs. @ 1.960 in. installed height
Valve Spring Open Pressure310 lbs. @ 1.370 in. open height
Valve Angle12 Degrees
Intake Valve MaterialTitanium, hollow stem (chrome nitride PVD coated)
Intake Valve Dia.2.205 in.
Intake Valve Weight77 grams
Exhaust Valve MaterialStainless steel (sodium filled)
Exhaust Valve Dia.1.610 in.
Exhaust Valve Weight74 grams
Timing Chain Part Number12646386 (single row chain)
Timing Chain Guide Style.Plastic Wedge Shaped Damper
Throttle Body, Fuel Injectors, Oil Pan Specs & More
Intake ManifoldCar-style, square port (LS7 specific)
Throttle Body90mm, 4-bolt, Silver blade (2006-08), Gold blade (2009-15)
Throttle ControlElectronic, Drive-by-Wire
Fuel Injector Part Number12576341
Fuel Injector Flow41.74 lb./hr. @ 58 psi
Flex Fuel Capable (E-85)No
Fuel Injector Length (between O-Rings)1.500 in.
Fuel Injector ConnectorEV6 / USCAR
Camshaft Sensor LocationTiming Cover
Oiling System/strong>
Dry Sump (8-10.5 qt. external tank capacity)
Oil Pan
Shallow center sump
Oil PumpStandard volume (0.96 c.i./rev.)
Oil Pump Pressure32.7 psi @ 1,000 rpm
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15 Comments

  1. Pingback: LS Engines 101: An Introductory Overview of the Gen III/IV LS Engine Family - OnAllCylinders

  2. Pingback: LS7 Engine Upgrade Guide: Expert Advice for LS7 Mods to Maximize Performance - OnAllCylinders

  3. This engine was also fitted to the limited edition HSV W427. A beast of a car!

  4. I’ve got a ’09 Z06 that for some reason just started missing…sitting in the driveway mind you! A noticeable tapping that was the initial indicator that something was wrong. When I revved the engine just a bit, I noticed the miss. This has never been an issue; the car has about 17K miles on it; I’m the original owner and I’ve never driven the car hard. I immediately shut the engine off and pushed it back in the garage. I’ve been reading/researching about the “valve drop” problem with the Z06’s. Been looking at options to address the valve drop problem….but torn between rebuilding the existing heads, or replacing with after market heads, which your article indicates is likely a better option. Dealership won’t touch pulling existing heads and installing after market heads. Senior Vette mechanic at dealership recommends rebuilding. I’m no expert, but know I’ve got to do something. Would really love to hear from experts who know the LS7 better than I do. Thoughts?

    • John, sorry to hear about the issue with your Z. If a new set of TFS 260’s with their revised geometry isn’t a possibility, the next be option is to rebuild your present heads.

      There are specialists who know exactly what needs to be done. Call Total Engine Airflow at 330-634-2155.

      They have a rebuild program where they replace the guides, exhaust valves, remanufacturer the Titanium intake valves, replace seats if necessary, and do a competition valve job. The price is reasonable and you will be good to go.

  5. Hi John,
    Prior to taking your cylinder heads off for a rebuild, I would get a mechanics stethoscope and pinpoint the noise location. Once located, pull that valve cover and inspect the rocker arms, see if a rocker may have unusual lash or no preload. Bring each rocker to the valve closed position to check, and try to push the rocker to force the lifter plungers to collapse. If something is unusual, investigate further… check that the rocker bolt is torqued. Check the valve spring ( they do break occasionally). Check pushrod tips and rocker cups… they can take it hard sometimes.
    Yes the LS7’s have exhaust valve issues, they can drop, and I’ve fixed a ton of them. Usually the drop happens at high rpm. Since you don’t abuse the engine, I suggest looking other places. When these heads are off, I Normally replace exhausts with a Manley or Ferrea valve.
    Ticking can be many things…. from a lifter plunger issue to an exhaust flange gasket leak. Since you have a distinct “miss”….check the exhaust header tubes with a heat gun (or touch with a saliva coated finger ;)…) when running. Isolate any dead cylinder(s). I can keep writing, however feel free to call. Ted at CNC Racing Heads. 630-917-2840

  6. Nathan Stahlwirth says:

    Hi John,

    My 2012 ran like crap out of nowhere, and it was all due to a spark plug wire that had worked itself loose. Check the cheap stuff before you go into the esoteric possibilities.

    Peace.

    Nathan

  7. Pingback: Ask Away! with Jeff Smith: Cam Swap Tech for 5.3L LS/Vortec Engines

  8. Dave Denver says:

    Could you check your specs on the LS7 please. I don’t know anyone who has an LS7 with piston oil-squirters in their corvette, including mine. I know the LS9 had the squirters but I’m sure the LS7 did not.

  9. Shannon Stockwell says:

    I’m rebuilding a close friend of mines 2013 z06 427 anniversary edition. Motor has been torn down and sent to machine shop. There are no oil squirters options on the 13 427,ls7,7.0 which ever you choose to call it. Now being a small town mechanic and engine enthusiast. I’d say for a professional as yourself that you dont know dick.

  10. Oh he knows dick. He’s trying to feed it to us all !

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