Intro to the LS9 and LSA

LS9

The LS9 was introduced in 2009 for the ZR1 Corvette. At the time, it was the most powerful engine ever produced by GM. It featured a 2.3L roots blower and made 638 hp.

The heads, block, and internals were all upgraded for strength. It also used a dry sump oiling system. The LS9 was available until 2013. It was replaced in 2014 by the LT4.

LSA

The LSA was introduced in 2009 for the Cadillac CTS-V. It was also available in the Camaro ZL1 in 2012. It was available in both cars until 2015.

The LSA was a scaled-back version of the LS9. It used a smaller blower making up to 580 hp. The LSA had less upgrades and wet sump oiling.

For specific details about these engines, please follow the links below:

• Chevy LSA Engine Specs
• Chevy LS9 Engine Specs
• Upgrading the LS9 and LSA Engines

Benefits

These engines were built for performance. The blocks were precision machined using deck plates. They also had piston oil squirters to improve durability.

The LSA and LS9 use rectangle port (LS3-style) cylinder heads. However, the heads were Rotocast for added strength. The engines both have a 4.065 in. cylinder bore. But, they used different main caps and head bolts.

What's the difference?

The easiest way to identify the engine is to check the 8th digit of the VIN code.

• Follow this link to Identify an LS Engine by VIN.

There are visual differences between the engines. The biggest difference is the supercharger.

Special Notes

• The LS9 engines were hand-built.
  • A plaque with the engine builder’s name is mounted on the driver’s side of the intercooler cover.
• The table below lists other external differences.