<Ul> <Li> Chevrolet Small - Block engine </Li> <Li> Northstar engine </Li> </Ul> <Li> Chevrolet Small - Block engine </Li> <P> The LS based GM small - block engine is the primary V - 8 used in General Motors' line of rear - wheel - drive cars and trucks . Introduced in January 1995, it is a "clean sheet" design with only rod bearings and bore spacing in common with the longstanding Chevrolet small block V8 that preceded it as the basis for GM small - block V8s . The basic LS variations use cast iron blocks, while performance editions are all aluminium with cast iron cylinder liners . </P> <P> The LS small - block has been manufactured in three Generations--III, IV, and V--with preceding Generations I and II of modular GM small - block engines having been based on the Chevrolet small - block V8 originally designed in 1955 . GM recycled the "LT" designation beginning with the LS Generation V "LT1" in 2014 . </P>

What year did the ls engines come into production