nah, just do a 3 inch pipe from the turbo back and u'll be all set

 

You mean with no cats or muffler? I don't want it to be that loud all the time.

My state allows any exhaust system that's complete (not sure if that means cats must be included), leak free, securely fastened, and not in excess of 95 decibels.

Are there any complete 3" systems that would comply with that?
Also, do any of them come with high flow headers?

 

Header* and you should just be able to add a resinator to lower the tone. Check borla, awe, miltek

 

well most of us take the risk when doing exhausts. start with a 3 inch down pipe if u cant get a full exhaust for whatever reason. it will be louder. i cant say how loud, but im 99% sure it'll be over 95db. mine sure as hell can be. especially when the motor is cold and it idles high. i try to keep it low, when i go to work early in the mornings. i shift super low to keep my rpm's down. the thng with exhaust noise is this: yes, they can get loud(n/a cars are actually louder than boosted ones) but most police vehicles are not equipped with a device to measure how loud it really is. the officer just says its loud and writes a ticket. so far i have no exhaust tickets for this car. i never got one for my previous car, but thats just luck, really. my car sounds like a track car past 4k, but im not at 4k that often or that much. a 3 inch system would be louder than a 2.5 inch, because it resonates more. most of us wont need a 3 inch pipe, because we dont have so much power that it NEEDS a 3 inch pipe, also most of us are not running diesel. ur car does not need or have a header. its got an exhaust manifold. those are different items. most of us will not need to change that piece, because once again, were not pushing that much hp. if u feel like u must do something, take it off and port it, polish it and gasket match it. if u get a larger turbo, then ud need a new larger manifold, so leave it be for now. i mean if the guys from apr can get 450hp out of their gti's by using their software ;imited to 12psi, oem everything, u can deal just fine with ur manifold.

 

The reason being, I actually do want to go BT in the future, just not any time soon. I do want a new exhaust sometime in the near future though, just to free up some horses. So I figured, why not get the complete exhaust system I'll need for my BT now? The exhaust system and manifold I would need for a BT would be compatible with my current ko3, right?

I'm still kinda' new to modding, so please let me know if my logic is flawed.

 

for a bt project u will need to rig up much more than just an exhast, u theoretically could build a 3 inch and keep most of it in place. to go bt, ull need to make a whole new manifold setup. you will also need to either go with twin sidemounts(like on my car) or twin front mount intercoolers. then u will need to completely redo all the intake and charge piping. intake manifold porting/polishing or goibg with a sheetmetal one would be in order. you will need to beef up oil lines for the turbos as not to fry them weekly. new software is a must, with a few hours on the dyno to dial that in right. most likely injectors, fuel pump, etc at this point ur better off sellin and buying an s4, thats already prebuilt with two turbos. what u should do instead is get a single large turbo. it'd be easier for somebody like you. two turbos does not always = more power. one big turbo running at 2bar is basically the same as running two smaller turbos running 1bar each. you end up with the same result. if ur new to modding, syart doing three things. 1- LOTS of reading. about how engines worlk, and turbos and how it affects the motor. read forums, books, magazines, websites, anything and everything u can find, 2- ask questions about modding in general and specific to your car. find out its weaknesses and strengths. 3-start saving cash. audis are expensive
if u want, talk to me on aim(same name as this). im on all day, im at home after some wrist surgery, i can tell u what i know. i am not an expert, but i'll be glad to share what i know with you or make some suggestions. soryy for bad spelling. i can only use 1 hand.

 

Lol, this whole time I thought BT stood for "big turbo". Sorry for being such a noob. I've read the stickies and quite a lot about the different turbo upgrades for the 1.8t. I definitely don't want twin turbos for my A4. I find the stickies to be an excellent guide to all the basics, but can't seem to find enough details about all the mods required to support a big turbo setup.

Don't worry about the spelling, my grandma just broke her wrist, and is having the same online grammatical issues. I'll be on AIM if my crappy internet connection supports it.

 

well, i'd say get the car chipped, buy a dv(definitely not a bov)u will not need anything fancy as far as those go. i am using oem ones for an audi tt and it works perfect. get a k&n intake filter. a downpipe would be great. then pick up a boost gauge, just to keep track of things and enjoy the car that way for a while. later when u save up some more cash, look into putting on a k04 turbo.