Autoaccessoriesreview is audience-supported. When you buy through links on this site, we may earn an affiliate commission that we use for site maintenance. Learn more

Blogs

LS2 vs LS3 vs LS7: What’s the Best Engine for You?

LS2 vs LS3 vs LS7
Written by Nick Steiner

The LS engines are a family of engines produced by General Motors. LS stands for “Luxury Sport,” These engines were designed with performance in mind. There are a variety of LS engines, including the LS2, LS3, and LS7.

Each motor has its unique features and benefits, and the differences in each of them can determine which engine you want to use in your next build or upgrade your current car.

LS2 engine pros and cons

ls2 engine pros and cons

The LS2 engine is a small block V8 that was introduced in 2004. It is an evolution of the LS1 engine, with a higher compression ratio and more power.

The LS2 was used in various GM vehicles, including the Corvette, Camaro, and Pontiac G8.

Pros

  • More potent than the LS1
  • Higher compression ratio
  • Used in a variety of GM vehicles

Cons

  • Some parts are not interchangeable with the LS1
  • More expensive than the LS1

LS3 engine pros and cons

LS3 engine pros and cons

The LS3 engine is a small block V8 that was introduced in 2008. It is an evolution of the LS2 engine, with a higher compression ratio and more power. The LS3 was used in various GM vehicles, including the Corvette, Camaro, and Pontiac G8.

Pros

  • More potent than the LS2
  • Higher compression ratio
  • Used in a variety of GM vehicles

Cons

  • Some parts are not interchangeable with the LS2
  • More expensive than the LS2

LS7 engine pros and cons

LS7 engine pros and cons

The LS7 engine is a small block V8 that was introduced in 2006. It is an evolution of the LS2 engine, with a higher compression ratio and more power. The LS7 was used in various GM vehicles, including the Corvette, Camaro, and Pontiac G8.

Pros

  • More potent than the LS2
  • Higher compression ratio
  • Used in a variety of GM vehicles

Cons

  • Some parts are not interchangeable with the LS2
  • More expensive than the LS2

LS2 vs LS3 vs LS7: How Do They Differ?

Key differences and similarities at a glance

Comparing points  LS2 LS3 LS7 Winner
Displacement 6.0L 6.2L 7.0L LS7
Engine material Aluminum Aluminum Aluminum None
Compression ratio 10.9:1 10.7:1 11:1 LS7
Piston stroke size 3.62″ 3.62″ 4″ LS7
Cylinder bore size 4.00″ 4.06 4.125″ LS7
Torque output  400 ft-lbs  425 ft-lbs  470 ft-lbs LS7
Power output  400 hp 430 hp 505 hp LS7
Intake Cathedral port Rectangular port Raised square port LS7
Exhaust 1-7/8″ headers 1-3/4″ headers 1-3/4″ headers LS7
Valvetrain OHV, two valves per cylinder OHV, two valves per cylinder DOHC, four valves per cylinder LS7
Oil system Wet sump Wet sump Dry sump LS7
Fuel system Sequential fuel injection (34lb/hr) Sequential fuel injection (42lb/hr) Sequential fuel injection (41.7lb/hr) LS3
Fuel type  Petrol  Petrol  Petrol None
Weight 517 lbs 536 lbs 545 lbs LS2
Reliability Reliable Very reliable Reliable LS3
Interchangeability Some parts are not interchangeable Some parts are not interchangeable Some parts are not interchangeable None
Price $6,000 $7,000-8,000 $10,000 LS2
Generations 2nd generation 3rd generation 4th generation LS7
Year 2004-2006 2008-2009 2006-2009 LS3
Emission Emissions compliant Emissions compliant Emissions compliant LS2

While there are many similarities between the 3 LS engines, quite a few differences need to be pointed out. These differences make one engine better than the other and depend on what you are going for when building your car.

The LS3 is the high-performance version of the LS engine family. It features an all-aluminum 6.2L (376 ci) engine and produces 430 hp at 5900 rpm and 424 lb·ft of torque at 4600 rpm. The LS3 was introduced in the 2008 Chevrolet Corvette.

The LS7 is the high-performance version of the LS engine family. It features an all-aluminum 7.0L (427 ci) engine and produces 505 hp at 6200 rpm and 470 lb·ft of torque at 4800 rpm. The LS7 was introduced in the 2006 Chevrolet Corvette Z06.

The LS2 is the budget performance version of the LS engine family. It features an all-aluminum 6.0L (364 ci) engine and produces 400 hp at 6000 rpm and 400 lb·ft of torque at 4400 rpm. The LS2 was introduced in the 2005 Chevrolet Corvette.

Here are the specs of each engine and which engine comes out on top in each area:

Displacement

LS2: 6.0L

LS3: 6.2L

LS7: 7.0L

Winner: LS7 because a larger displacement engine usually means more power.

Engine material

LS2: aluminum

LS3: aluminum

LS7: aluminum

Winner: None

All of the engines are aluminum; however, the rods and crankshafts can be made from different materials, so keep an eye out for that when you are working on these engines.

Compression ratio

LS2: 10.9:1

LS3: 10.7:1

LS7: 11:1

Winner: LS7 because a higher compression ratio means more power and efficiency. The LS2 and LS3 are very close, yet the LS3 outputs more power despite having a lower compression ratio due to being a newer and more efficient engine.

Piston stroke size

LS2: 3.62″

LS3: 3.62″

LS7: 4″

Winner: LS7 because a more significant stroke means more power. The LS2 and LS3 have the same stroke size.

Cylinder bore size

LS2: 4.00″

LS3: 4.06″

LS7: 4.125″

Winner: LS7 because a larger bore means more power. The LS2 and LS3 are very close in size.

Torque output

LS2: 400 ft-lbs

LS3: 425 ft-lbs

LS7: 470 ft-lbs

Winner: LS7 because more torque means more power. The LS2 and LS3 are very close, with the LS3 coming out slightly ahead.

Power output

LS2: 400 hp

LS3: 430 hp

LS7: 505 hp

Winner: LS7 because more horsepower means more power. The LS2 and LS3 are close but the LS3 is slightly better.

Intake

LS2: cathedral port

LS3: rectangular port

LS7: raised square port

Winner: LS7 because a raised square port is more efficient than a cathedral or rectangular port.

Exhaust

LS2: 1-7/8″ headers

LS3: 1-3/4″ headers

LS7: 1-3/4″ headers

Winner: LS7 because a larger exhaust means more power. The LS2 and LS3 are very close and are almost the same engine.

Valvetrain

LS2: OHV, two valves per cylinder

LS3: OHV, two valves per cylinder

LS7: DOHC, four valves per cylinder

Winner: LS7

The winner was chosen because four valves per cylinder are more efficient than two valves per cylinder. The LS2 and LS3 are very close and are almost the same engine.

Oil system

LS2: wet sump

LS3: wet sump

LS7: dry sump

Winner: LS7

The winner was chosen because a dry sump is more efficient than a wet sump. The LS2 and LS3 are very close and are almost the same engine.

Fuel system

LS2: sequential fuel injection (34lb/hr)

LS3: sequential fuel injection (42lb/hr)

LS7: sequential fuel injection (41.7lb/hr)

Winner: LS3

All of the engines use a sequential fuel injection system. However, their fuel flows vary, with the LS3 having the most flow and the LS2 having the least flow.

Fuel types

LS2: petrol

LS3: petrol

LS7: petrol

Winner: None

All of the engines take the same kind of fuel. Premium gasoline is what you should put into any of these engines if you want the most power and best efficiency.

Weight

LS2: 517 lbs

LS3: 536 lbs

LS7: 545 lbs

Winner: LS2

The winner was chosen because a lighter engine means better performance with a higher power-to-weight ratio.

Reliability

LS2: very reliable

LS3: very reliable

LS7: very reliable

Winner: LS3 because reliability is an essential factor in engine performance. The LS3 is the newest engine, and with the advances in technology, it should be the most reliable out of the 3.

Interchangeability

LS2: some parts are not interchangeable

LS3: some parts are not interchangeable

LS7: some parts are not interchangeable

Winner: None because interchangeability means that the engine is easier to modify. You will have to look up each part to determine whether or not it is interchangeable.

Price

LS2: $6,000

LS3: $7,000-8,000

LS7: $10,000

Winner: LS2

The winner was chosen because the price is very important when buying an engine. The LS2 is the cheapest engine out of the three.

Generations and years

LS2: 2nd generation, 2004-2006

LS3: 3rd generation, 2008-2009

LS7: 4th generation, 2006-2009

Winner: LS3 because a more recent engine is more efficient.

Emissions

LS2: emissions compliant

LS3: emissions compliant

LS7: emissions compliant

Winner: LS2

All of the engines are emissions compliant but due to the LS2 using the least amount of fuel, it disperses the least amount of emissions. That means you won’t be polluting the air nearly as much as the other two engines.

LS2 vs LS3 vs LS7: What’s best for whom?

The LS2 engine is your go-to choice if you want a robust and reliable engine at a reasonable price.

The LS3 engine is perfect for those who wish to have even more power and are willing to pay a bit more for it.

On the other hand, the LS7 is best for those who want the most power and won’t mind paying a premium.

About the author

Nick Steiner

Nick has been a car nut for his whole life as far as he can remember. His father was a car dealer who used to change and repair his cars himself. As a result, Nick had the opportunity to get around all sorts of cars and learned to get his hands dirty repairing vehicles from an early age.

Nick is a great fan of Japanese quality and German preciosity. His deep passion lies in older models that he believes have a flair that takes him back to his childhood. He also loves their durability and reliability when compared to the modern models.

Leave a Comment