I think Henz would be on the money. He has better mods than me (Plaz Plenum, BF engine etc) and I made 420wkw on the dyno while tuning for the new exhaust. @dragonf6 Not sure of the exhaust on the F6 but I would do the exhaust first if I was to mod another BF because I think it's important to get all the used, hot gases out easily and avoid constipation with less turbo heat and lower boost/power ratio. I tried pushing more in than what could escape easily and it didn't end well. 330-340wkw is a fairly respectable goal so the safer the better in my opinion.