Cars Simplified: Everything Automotive Explained

LS Engines

The LS series of engines is built by and designed by Tom Stephens and Ed Koerner. They are gasoline-powered V8 engines that feature an aluminum or iron block and heads, a pushrod engine layout, a 90° angle piston bank arrangement, and are relatively small for their displacement amount.


The LS1 was introduced as the standard engine in the Corvette for the 1997 model year.

A Stock LS1 Pontiac GTO Dyno Run

Footage of a 2004 Pontiac GTO on a Mustang dyno, uploaded on October 13, 2018, and filmed at East Windsor, Connecticut.


The LS6 has the same displacement as the , but with different cylinder heads for improved intake and exhaust flow.


The LS2 became the standard engine for the Corvette and GTO in 2005, replacing the . The engine is equipped with the same "243" head casting as the . The engine typically produced about 400 HP and shows up as a "U" engine VIN code.

LS2 Engine Data

Displacement:6.0L (364 CI)
Compression Ratio:10.9:1
Typical Output:400 HP
Piston Material:Hypereutectic Cast Aluminum Alloy
Oil System:Wet Sump
Throttle Control:Electronic

Steve's Thoughts on the LS2 Engine

As an owner of a 2005 Pontiac GTO, I've experienced the LS2 as a factory engine. While the LS line is known for its engine swap potential, I have yet to perform an LS swap myself. However, as a stock engine, the LS2 is a powerful yet reliable engine. It is well deserving of its status as an iconic American V8.


- , June 20, 2023


The LS7 is a 7.0L V8 performance engine. It has both a larger bore and stroke than the before it. The LS7 is hand-built by the General Motors Performance Build Center in Wixom, Michigan.

LS7 Engine Data

Displacement:7.0L (427.8 CI)
Compression Ratio:10.9:1
Oil System:Wet Sump

Replacing an LS Water Pump

The LS engine has a water pump mounted to the center of the front of the engine. Some models have a belt tensioner mounted to them, and also have the thermostat/water outlet mounted to it. The pump is attached with six bolts, with three per gasket/side.

Replacing a Thermostat on an LS2, LS3, or LS7 Engine