Yeah 15bhp isn't a whole lot of difference, especially when you can get a C&L or Demolet intake and a SCT-2 tuner and have nearly 200rwhp right off the bat. Add in the weight difference and there you go. Here's something you might like to see: http://american-speed.com/collective/forums/showthread.php?t=87 Our guy ricklmesa at the 4.0 Collective dynoed his car at 213RWHP and 242RWTQ. His only mods were an MMR Intake, JBA duals w/x-pipe (not sure if it was catted or not) and then he took his car in for a custom tune. 213rwhp and 242rwtq is crazy with three mods and a tune don't you think? I don't know how much RWHP the stock 1999-2004 GT's put out, but I bet it's really close to what this 4.0 is running.