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.
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
- 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
- Doweled, billet steel main caps
- Forged steel crankshaft
- Titanium connecting rods
Other Performance Features
- Block machining performed using deck plates to increase accuracy
- 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
|Horsepower Rating||505 hp @ 6,300 rpm|
|Torque Rating||470-481 ft./lbs. @ 4,800 rpm|
|Engine Weight||454 lbs. (assembled with clutch, flywheel, balancer, and water pump)|
|VIN 8th Digit||Year||Make||Model|
|E||2006-13||Chevrolet||Corvette Z06 and
Corvette 427 (2013)
|LS7 Engine Block Specs|
|Displacement||7.0L / 427 c.i.d.|
|Cylinder Liners||Pressed in, 5.850 in. long (vs. standard 5.500 in.) to support longer stroke|
|Bore Dia.||4.125 in.|
|Deck Height||9.240 in.|
|Bore Spacing||4.400 in.|
|Thrust Bearing Location||#3 Main|
|Main Cap Style||Doweled, 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 Squirters||Yes|
|Cam-to-Crank Centerline||4.914 in.|
|LS7 Rotating Assembly Specs|
|Piston Material||M142 cast aluminum alloy (with anti-friction coating and anodized top ring groove)|
|Piston Style||Flat top, with valve reliefs|
|Wrist Pin Dia.||0.925 in. (Full Floating)|
Rod Part Numbers
|12586258, 126318172, 12661677|
|Connecting Rod Material||Titanium|
|Connecting Rod Style||I-beam, with tapered small end|
|Connecting Rod Length||6.067 in.|
|Connecting Rod Housing Bore||2.225 in.|
|Connecting Rod Bolts||M9 x 1 x 40|
|Connecting Rod Weight||464 grams|
|Crankshaft Material||Forged 4140 steel (early), Forged 44MNSIVS steel (late)|
|Crankshaft Part Numbers||12611649 (2006-11),
|Crankshaft Weight||56.40-57.65 lbs.|
|Crankshaft Main Journal Dia.||2.559 in.|
|Crankshaft Rod Journal Dia.||2.100 in.|
|LS7 Cylinder Head Specs|
|Combustion Chamber Volume||70cc, CNC-ported|
|Intake Port Shape||Raised square port, CNC-ported|
|Intake Runner Volume||259cc|
|Exhaust Port Shape||D-port, CNC-ported|
|Exhaust Runner Volume||86cc|
|Valve Seat Material||PMF 28 / Brico 3220|
|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|
|LS7 Cam Specifications|
|Camshaft Part Number||12638426|
|Duration @ .050 in. (int./exh.)||210°/230°|
|Valve Lift||0.593 in./0.589 in|
|Cam Advance||-3 degrees|
|Cam Gear Attachment||3-bolt|
|Cam Gear Poles||4X|
|LS6 Valvetrain Specs|
|Lifter Style||Hydraulic roller (with ceramic check ball for high rpm operation)|
|Lifter Link Style||Plastic Lifter Tray|
|Lifter Body Diameter||0.842 in.|
|Pushrod Length||7.750 in.|
|Pushrod Dia.||0.375 in.|
|Rocker Arm Mounting Style||Pedestal|
|Rocker Arm Style||Die-Cast, Roller Fulcrum|
|Rocker Offset||Intake only, 9mm total offset|
|Valve Spring Style||Beehive (LS7 specific)|
|Valve Spring Color||Natural|
|Valve Spring Seat Pressure||100 lbs. @ 1.960 in. installed height|
|Valve Spring Open Pressure||310 lbs. @ 1.370 in. open height|
|Valve Angle||12 Degrees|
|Intake Valve Material||Titanium, hollow stem (chrome nitride PVD coated)|
|Intake Valve Dia.||2.205 in.|
|Intake Valve Weight||77 grams|
|Exhaust Valve Material||Stainless steel (sodium filled)|
|Exhaust Valve Dia.||1.610 in.|
|Exhaust Valve Weight||74 grams|
|Timing Chain Part Number||12646386 (single row chain)|
|Timing Chain Guide Style.||Plastic Wedge Shaped Damper|
|Throttle Body, Fuel Injectors, Oil Pan Specs & More|
|Intake Manifold||Car-style, square port (LS7 specific)|
|Throttle Body||90mm, 4-bolt, Silver blade (2006-08), Gold blade (2009-15)|
|Throttle Control||Electronic, Drive-by-Wire|
|Fuel Injector Part Number||12576341|
|Fuel Injector Flow||41.74 lb./hr. @ 58 psi|
|Flex Fuel Capable (E-85)||No|
|Fuel Injector Length (between O-Rings)||1.500 in.|
|Fuel Injector Connector||EV6 / USCAR|
|Camshaft Sensor Location||Timing Cover|
|Oiling System/strong>||Dry Sump (8-10.5 qt. external tank capacity)|
|Oil Pan||Shallow center sump|
|Oil Pump||Standard volume (0.96 c.i./rev.)|
|Oil Pump Pressure||32.7 psi @ 1,000 rpm|
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.