About The LS Engine Family

The General Motors LS and Vortec engine platform is a series of small-block V8 engines that were introduced in the late 1990s and remained in production until the mid-2010s. These engines have gained immense popularity among car enthusiasts and racers due to their performance potential, versatility, and relatively compact design. The LS and Vortec engines come in various displacements, materials, and configurations, catering to a wide range of applications including trucks, performance cars, and even marine use. Below is an overview of the various generations and types of engines, as well as a list of known engine RPO (Regular Production Option) codes from 1997 to 2014. At Howell EFI, we specialize in making wiring harnesses to make swapping these modern LS or Vortec fuel injected small block V8 engines into any vehicle using OE quality components.

Generations and Types:

Known Engine RPO Codes (1997-2014):
(Note: This list might not be exhaustive but includes many of the notable RPO codes for the LS and Vortec engines during this period that we make harnesses for.)

Remember that some RPO codes may vary depending on the year, vehicle application, and market. Additionally, the LS engine platform has seen numerous custom builds, swaps, and modifications, leading to a wide array of variations beyond the listed RPO codes.

RPO Engine Code	Howell PN#	HP/TQ	Years	Vehicle(s)	Block	Heads
LS1 5.7L (Gen III)				Camaro/Firebird, Corvette	Aluminum	Cathedral
LS6 5.7L (Gen III)				Corvette	Aluminum	Cathedral
LQ4 6.0L (Gen III)				Trucks/Vans	Iron	Cathedral
LQ9 6.0L (Gen III)				Trucks/Vans	Iron	Cathedra
LM7 5.3L(Gen III)				Trucks/Vans	Iron	Cathedral
L59 5.3L (Gen III)				Trucks/Vans		Cathedral
L33 5.3L (Gen III)				Trucks/Vans	Aluminum	Cathedral
LR4 4.8L (Gen III)				Trucks/Vans		Cathedral
LS2 6.0L (Gen IV)				Corvette, GTO	Aluminum	Cathedral
LS3 6.2L (Gen IV)				Corvette, Camaro, G8, SS	Aluminum	Rectangle
L99 6.2L (Gen IV)				Camaro	Aluminum	Rectangle
LS7 7.4L (Gen IV)				Corvette Z06	Aluminum	Rectangle
LSA 6.2L Supercharged (Gen IV)				Camaro, CTS-V	Aluminum	Rectangle
LS9 6.2L Supercharged (Gen IV)				Corvette ZR1	Aluminum	Rectangle
L92 6.2L (Gen IV)				Escalade/Denali	Aluminum	Rectangle
L94 6.2L (Gen IV)				Escalade/Denali	Aluminum	Rectangle
L77 6.0L (Gen IV)				G8, Caprice PPV	Aluminum	Rectangle
LY6 6.0L (Gen IV)				Trucks/Vans	Iron	Rectangle
L96 6.0L (Gen IV)				Trucks/Vans	Iron	Rectangle
LC9 5.3L (Gen IV)				Trucks/Vans	Aluminum
LH6 5.3L (Gen IV)				Trucks/Vans	Aluminum
LMF 5.3L (Gen IV)				Trucks/Vans
LS4 5.3L (Gen IV)				Impala, Monte Carlo	Aluminum		FWD
LFA 6.0L				Trucks/Vans			Hybrid

Gen III (1997-2007):

• The Gen III engines were introduced in the late 1990s and marked a significant departure from the traditional small-block design.
• These engines feature all-aluminum construction, electronic throttle control, and coil-on-plug ignition.
• Some notable engines in this generation include the LS1, LS6, and LM7.

Gen IV (2005-2014):

• The Gen IV engines continued the evolution of the LS platform with improved efficiency, power output, and emissions control.
• This generation saw the introduction of features like variable valve timing (VVT) and Active Fuel Management (AFM), which shut down half of the cylinders under light load conditions to save fuel.
• Engines in this generation include the LS2, LS3, L92, and LSA, among others.

Iron and Aluminum Truck Engines:

• The LS and Vortec engine platform also includes truck-specific engines, which are designed to provide strong low-end torque for towing and hauling.
• These engines are available in both iron and aluminum blocks.
• Examples include the LQ4 (6.0L iron block), LQ9 (6.0L iron block), and LY6 (6.0L iron block).

Factory Supercharged LS Engines:

• The LSA engine is a notable example of a factory supercharged LS engine.
• It features a 6.2L displacement and a supercharger, making it an excellent choice for high-performance applications.
• The LSA engine is often found in vehicles like the Cadillac CTS-V and Chevrolet Camaro ZL1.

7.0L LS7 Engine:

• The LS7 engine is a high-performance naturally aspirated engine with a 7.0L displacement.
• It’s known for its use in the Chevrolet Corvette Z06 and delivers impressive power and torque output.

LSX Engines:

• The LSX is a performance-oriented version of the LS engine designed for high-horsepower applications and motorsports.
• These engines often have larger displacements and stronger components compared to regular LS engines.
• They’re used in various racing applications, including drag racing and road racing.
• Popular LSX crate engines are the LSX 454, LSX B8, LSX B15 designed for boosted applications.