Ok so i got my VT about 5 months ago, the first couple of months i was taking her to tracks and pushing her hard (she likes it) and i noticed plenty of carbon goop/crud/residue whatever u call it around the exhaust tip. So i decided to drive like an 87 year old woman for like a month just to see the difference...and to my surprise, was very minimal. I'm not sure if it's because i need a catch can or is it because the engine its just running too rich?? (2 much O2 x fuel ratio). Any can its better than none, but I don't know if its gonna make a big difference or what type of filter (mesh pads, bronze filter, SOS pad??) This is my 1st GDI and so far very pleased w/it. But i know that it's bypassing many components in order to inject the fuel and provide a faster burn and all that residue left inside concerns me. I plan on taking her to the 250-300 hp window (tune and big turbo eventually) so i would prefer not to have to buy twice. If you know, think, or have installed something to prevent this please feel free to post. Thnx.