i have worked on both and yes the ls motors or really nice piece of work and well layed out but both types f motors have their pros and cons ..... i have run with many ls with my LT1 so yes maybe they do make more power from the factory but good cam and heads make the lt1's fly just like any other small block chevy..... the ls one don't require as much work to push the 400 hp mark usually cam and long tubes.... but the lt1 can run with the best of them ...