Contents
LS4 Engine Specs
Here in this article, you will learn about the LS4 Engine Specs, Performance, Bore & Stroke, Cylinder Heads, Cam Specs & More, Let’s discuss the LS4 Engine Specs, Valvetrain, performance, and Reviews.
For GM vehicles manufactured between 2005 and 2009, the LS4 engine was a Gen. 4 5.3-liter aluminium small-block motor.
The only LS engine ever installed in front-wheel-drive automobiles makes this one special.
The cylinder heads of the LS4 utilized Active Fuel Management and were designed to look like a cathedral (AFM).
Both flex-fuel (E85) capability and variable valve timing (VVT) technology were absent from the engine design.
Because of their mechanical similarity, the LS and LS-based Vortec engines from General Motors ended up in nearly every brand in the GM stable, including Chevrolet, Pontiac, GMC, Cadillac, Buick, and even Saab, Hummer, and Isuzu.
Since LS and Vortec engines are easy to find, they have become the standard for performance and swap applications.
The addition of turbochargers, superchargers, high-flow cylinder heads, intake systems, cams, and nitrous oxide to these engines can result in significant power gains.
LS4 Block Specs |
|
---|---|
Casting Number | 12569004 |
Material | Aluminium |
Displacement | 5.3L / 325 c.i.d. |
Bore Dia. | 3.780 in. |
Stroke | 3.622 in. |
Deck Height | 9.240 in. |
Bore Spacing | 4.400 in. |
Thrust Bearing Location | #3 Main |
Main Cap Style | 6-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 Centerline | 4.914 in. |
LS4 Engine Ratings |
|
---|---|
Compression Ratio | 10:1 |
Horsepower Rating | 303 hp |
Torque Rating | 323 ft.-lbs. |
LS4 Cylinder Head Specs |
|
---|---|
Casting Numbers | 799, 243 |
Material | Aluminium |
Combustion Chamber Volume | 65cc |
Intake Port Shape | Cathedral |
Intake Runner Volume | 210cc |
Exhaust Port Shape | D-Port |
Exhaust Runner Volume | 75cc |
Intake Valve Diameter | 2.000 in. |
Exhaust Valve Diameter | 1.575 in. |
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 |
LS4 Valvetrain Specs |
|
---|---|
Lifter Style | Hydraulic Roller |
Lifter Link Style | Plastic Lifter Tray |
Lifter Body Diameter | 0.842 in. |
Pushrod Length | 7.385 in. |
Rocker Arm Mounting Style | Pedestal |
Rocker Arm Style | Die-Cast, Roller Fulcrum |
Rocker Ratio | 1.7 |
Rocker Offset | None |
Valve Spring Style | Beehive |
Valve Spring Color | Natural |
Valve Angle | 15 Degrees |
Intake Valve Material | Steel, Solid Stem |
Intake Valve Dia. | 2.000 in. |
Exhaust Valve Material | Steel, Solid Stem |
Exhaust Valve Dia. | 1.575 in. |
Timing Chain Guide Style (2005-06) |
Plastic |
Timing Chain Guide Style (2007-09) |
Spring Loaded Tensioner |
LS4 Rotating Assembly Specs |
|
---|---|
Piston Volume | 0cc |
Wrist Pin Dia. | 0.9431 in. (Full Floating) |
Connecting Rod Material | Powdered Metal |
Connecting Rod Style | I-Beam |
Connecting Rod Length | 6.098 in. |
Connecting Rod Housing Bore | 2.225 in. |
Connecting Rod Bolts | M9 x 1 x 43 |
Connecting Rod Part Number |
12649190 |
Connecting Rod Casting Number (Last 3 Digits) |
143 |
Crankshaft Material | Cast Iron |
Crankshaft Part Number | 12568920 |
Crankshaft Casting Number (Last 3 Digits) |
216 |
Crankshaft Main Journal Dia. | 2.559 in. |
Crankshaft Rod Journal Dia. | 2.100 in. |
Crankshaft Length | 13mm Shorter than Standard (-10mm snout, -3mm rear flange) |
Reluctor Wheel (2005-Early 2007) |
24X |
Reluctor Wheel (Later 2007-09) |
58X |
Piston Material | Hypereutectic Cast Aluminum Alloy |
Piston Style | Flat Top |
LS4 Applications |
|||
---|---|---|---|
VIN 8th Digit | Year | Make | Model |
C | 2005-08 | Pontiac | Grand Prix GXP |
C | 2006-07 | Chevrolet | Monte Carlo SS |
C | 2006-09 | Chevrolet | Impala SS |
C | 2008-09 | Buick | LaCrosse Super |
Other Key LS4 Specs
Intake Manifold Part Number | 12604786 |
Intake Manifold | Car-Style (Reversed) |
Intake Manifold Part Number (2005-07) |
12568580 |
Intake Manifold Part Number (2008-09) |
12631016 |
Throttle Body | 76mm, 4-Bolt, Gold Blade (Non-standard Bolt Pattern) |
Throttle Control | Electronic, Drive-by-Wire |
Fuel Injector Part Number | 12580681 |
Fuel Injector Flow | 30 lbs./hr. @ 58 psi |
Fuel Injector Length Between O-Rings | 1.73 in. |
Fuel Injector Connector | EV6 / USCAR |
Computer (2005-2007) |
E40 |
Computer (2007-09) |
E67 |
Crankshaft Reluctor Ring (2005-Early 2007) |
24x |
Crankshaft Reluctor Ring (2007-09) |
58x |
Camshaft Sensor Location | Timing Cover |
Oil Pan | Centred Sump |
Oil Pump | High Volume, 1.25 c.i./rev. |
LS4 Engine Specs Review Video
LS4 Engine Specs FAQ
What size motor is a LS4?
General Motors LS4 is a popular option for those shopping for a large car engine.
The LS4 is the sole small block engine available in a transverse layout, and it has a displacement of 5.3 litres in a V8 configuration.
Is the LS4 engine a good engine?
Unless you’re doing a swap into an FWD vehicle or a mid-engine kit car, the LS4 isn’t the best option for an engine.
Get the thermostat set to 160 degrees before visiting the chassis dyno tuner, since this will increase the available tuning range.
What does the LS4 come in?
The LS4 was GM’s fourth-generation, 5.3-litre (L) aluminium small block engine, installed in vehicles from 2005 to 2009.
As the only LS engine ever installed in a front-wheel-drive car, it has a distinct place in history.
The LS4 employed active fuel management and had cylinder heads with a cathedral port design (AFM).
Is the LS4 a Corvette engine?
Finally, General Motors offered a 454-ci LS4 engine for the Corvette in 1973.

I am Dipak Salvi. I’ve been a blogger since 2010, and I love to write. I really like to write about cars, technology, and money. I also write about fitness and health. I run a lot of blogs, such as https://commercialvehicleinfo.com. You can contact me at [email protected]