Differences in Lincoln ls First and Second gen engines.

[Logan G]

I've noticed that the second gen Lincoln Ls engines make about 280 Hp, While the First Gen only makes 252 Hp. What is the differences in these engines? I've done research and the engine size is the same. Why does the second gen make about 30 more horse? Camshafts? Progression of electronics over the years? Thanks in advanced All!