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
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
- 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 Ratio | 11:1 |
| 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) |
LS7 Applications
| VIN 8th Digit | Year | Make | Model |
|---|---|---|---|
| E | 2006-13 | Chevrolet | Corvette Z06 and Corvette 427 (2013) |
| E | 2014-15 | Chevrolet | Camaro Z/28 |
| LS7 Engine Block Specs | |
|---|---|
| Casting Number | 12598723 |
| Material | 319-T7 aluminum |
| 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. |
| Stroke | 4.000 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 |
| Piston Volume | +7cc |
| Wrist Pin Dia. | 0.925 in. (Full Floating) |
| Connecting 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), 12641692 (2012-15) |
| Crankshaft Weight | 56.40-57.65 lbs. |
| Crankshaft Main Journal Dia. | 2.559 in. |
| Crankshaft Rod Journal Dia. | 2.100 in. |
| Reluctor Wheel | 58X |
| LS7 Cylinder Head Specs | |
|---|---|
| Casting Number | 12578452 |
| Material | 356-T6 Aluminum |
| 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 |
| Lobe Separation | 120° |
| 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 Ratio | 1.8 |
| 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.
[…] LS7 Engine Specs: Performance, Bore & Stroke, Cylinder Heads, Cam Specs & More […]
Ls7 is a big block 454 not a small block. Chevy should have named the small block different.
Not in the least. The LS7 is based on the LS design and share most dimensions and many parts with the rest of the LS family, while sharing NONE of those features with the old school big block rat motor 454.
[…] [Every engine spec you’ll need can be found here: LS7 Engine Specs: Performance, Bore & Stroke, Cylinder Heads, Cam Specs & More.] […]
This engine was also fitted to the limited edition HSV W427. A beast of a car!
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.
One option is buying a set of heads from the GM parts department. The late model heads in my opinion, are of better quality. I own a 08 Z06. I had 26k on the engine, and had a lifter mushroom, in the bore. Had warranty, the dealership could not repair the engine. The 08 engine was replaced by a later model in 2016. I have about 30k on the late model engine. Runs great.
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
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
[…] cam and induction and a set of headers and then added the LS9 cam, which is very similar to the LS7. The good news is that he picked up an amazing 60 horsepower with this swap. His engine made a […]
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.
Dave, you are right.
I wanted to install squirters, then found out I had them, then found out I didnt.
I run a supercharger and surely want to have squirters. I really would like to know just how important they are.
Contact Thomson Automotive in Wixom, Mi.. They can install piston oil squirters (in the form of Holley carburetor air bleed jets) in N LS7
2006 Z06 with a LS7 with piston squirter. I did not take any pictures, simply because I didn’t have anything to prove. My car had 22,327 miles on it when I upgraded engine to run with turbos. Anyway it has a little over 32,000 miles with turbos and oil squirters on the pistons.
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.
Even if the girl made a mistake she should at least correct it.
Im beginning to think summit is only making blogs for ranking not because they love to talk tech.
Oh he knows dick. He’s trying to feed it to us all !
I want 7.0
5 set
Full head component
Can I fix it on 5.7 block
[…] people want an LS7, LS3 or even an LS2. Heck, most would take an L92, L76 or even an iron-block LQ4 for that […]
[…] and Chevrolet Performance MLS head gaskets. Matt reused the factory rocker arms and dropped in new LS7-style lifters. Even though the heads were decked, he lucked out and was able to use stock-length […]