I think I know what exhaust cutout/bypass you are talking about. I thought I had it saved on my favorites but its not there. There is a couple different manufacturers out there. The one I saw was actually pretty much made just for TT's, it was all stainless steel and was boost/vacuum operated. It dumped right off the downpipe if you hammered on it, but ran through the stock exhaust while cruising. There is a lot of electronic cut-outs that use a swtich. I searched yahoo and found quite a few, it makes me mad though I cant find the one that was on the 225Q....I will look more after work.[:@]

 

Hopefully someone can find it.

It's driving me nuts i can see the web site in my minds eye.