The LS1 title identifies Corvettes with that model engine. The LS1 is a V-8 engine used in late-model Corvettes, from 1997 and up, and F-body cars (Firebird, Camaro.) It is a solid engine that was meant for high muscle car performance. According to the Corvette owner's manual, only synthetic oil should be used with this engine.
The LS1 engine requires a unique oil that meets GM Standard GM4718M. Oils that meet this standard are known as synthetic, and they also meet the standards for the American Petroleum Institute certification for gasoline engines. It's important to note that not all API-approved oils meet GM Standard GM4718M.
SAE 5W-30 is the oil that is the best viscosity for the LS1, according to the owner's manual. Do not use SAE 20W-50 or other viscosity oils.
The car is filled with "Mobile 1 Synthetic" oil from the factory. GM mechanics are likely to use this brand.
