Check your cats...
And I don't mean the kind that meow. I have a whipple w/kooks headers & high flow cats. Well I've been working 12-hour days so haven't had any time to work on my car but I started to notice some exhaust leaks and the motor was feeling a bit "flat" I finally took a look at the cats and they were destroyed. I didn't take pics, but the centers were detached from the housing and a lot of it was melted...not pretty. I think the general consensus is not to run cats w/higher hp motors anyway, but just throwing this out there as an FYI.