a 5.7 vortec was also based on the same engine platform as the 265 from way back, i doubt you'll hear anyone with that engine referring back to a 265. when they built the LS1 engine, they set out to build a new small block platform (the gen III). the corvette just happened to be the best place to showcase and test the new engine with it having a full re-design that year and the new body style truck not coming out for another 2 years.