The LS1 was the first Gen-3 LS engine produced by GM and was released in the '97 C5 Corvette. The engine displaces 5.7 liters and has the same bore spacing, but shares nothing else with the Gen-1 and Gen-2 engines.
The new Gen-3 construction features aluminum block construction using 6 bolt mains and steel cylinder liners. Cylinder heads were completely redesigned featuring cathedral intake ports, composite intake manifold, and coil on plug ignition. It later was produced for Camaro and GTO and used in the Corvette until 2004.