I went from a true 800HP BBC that would rev to 8K to a 418 Ls3 making 630 HP and am much happier...although I went TKO 600 to auto so that torque multiplication makes a big difference. The car is smoother, quieter, better in traffic and feels 90% as fast. The only time it feels like it's slower is over 100mph when the 540 would just keep pulling until you ran out of balls. This one pulls but it starts to slow down at triple digits a bit. Plus I now get 22mpg compared to my previous best of 10 with the efi BBC.