Hey guys! Long time no post so I'll change that quickly with a long one (sorry in advance). My 02 A4 1.8T just hit 197k with a destroyed cat and rear o2 sensor (intake leak on turbo sucked oil through everything). i just purchased a timing belt kit, race/test pipe, bosch 02 sensor and a manual transmission service kit from ECS Tuning. I currently do not have an aftermarket exhaust, chip, intake or anything. Pretty much bone stock because of the mileage I bought the car at (136K). Now I know that several people on here have the test pipe and some of you throw CELs and some dont. For those of you who have the test pipe and do not have a CEL what did you do? There are bungs already welded on the test pipe but should i get a couple extras? Im due for emissions and luckily CT does not sniff the exhaust but they do do a visual check on the cat (me and my mechanic will solve that by tacking on heat shields to cover the "off road use only" test pipe). So my main questions are: What do you guys (who have test pipes with NO CEL) do to make it not throw a code? Will the sound of my stock exhaust change? I will be purchasing an aftermarket exhaust in the near future along with some aftermark Alzor rims and some lowering springs/struts. Thanks in advance everyone!

P.S. just convinced my brother to buy a 2003 Audi A4 1.8T Quattro (red, sport package, 5MT) and he loves it! (Marutski3)