3 inch is loud as hell and very unnesseacry (spelleing). You will probably not like it at all. Just get a test pipe or high flow cat with an ECU tune and you will be happy. Stock size is perfectly fine for stock turbo unless you want the loud sound.

 

Well the bigger the pipe the louder, thats correct, but it also depends on what muffler/s he puts on the car. Diesels (like on my work van) with a 3.5" exhaust isn't that loud because of the bath tub muffler on it.
If he ran two straight thru mufflers (like most systems sold, neuspeed, APR, Milltek etc.)
it will be relatively quiet. Personally i think the 2.0T goes like a bad out of hell with a 3" pipe VS stock, even with the stock turbo. I remember an A3 that came in with a 3" APR exhaust with a chip and it was damn quick. Slightly loud, but not bad enough where i would mind driving down the road. Mine is almost 3" on my neuspeed exhaust and its not loud at all running a 3 inch test pipe.

 

Hey, if anyone is interested I plan on doing a GB on the new ER exhaust for the B7 A4 2.0t. It will be a small GB (5-10). Retail will be $1245 + shipping, I might be able to make the GB 15% off that depending on how much interest there is for the exhaust.

ER exhaust info:

Dual Muffler, Quad Tips *Requires S4 rear valance
True 3” to dual 2.25” Cat back exhaust

 

if you're keeping the engine stock, a high flow cat or cat back won't get you any extra power.

 

well thanks for the info i will probably invest into a full exaust rather than try to piece together a system and then have to upgrade after a turbo or chip upgrade

 

Stock exhaust is fine for anything you can throw at the stock turbo except the cat area. You will need that to go stage 2 or stage 2+ . Exhaust is like 2.3 inches stock. You will only feel a big bennefit on a turbo upgrade.

 

ive never priced out a hfc or test pipe but the test pipe i could manage myself, just an empty pipe in place of the cat right? catsare not cheap so im assuming a hfc isnt either, i like the idea of not tripping my o2s at least until i chip...

 

$295 for a 250 cell HFC.

 

thanks man that helps out, i appreciate all the possitive feedback from u guys, i really want to take my car to the next step(turbo!!!!) but with a wife and kid and being 21 i will have to take small hp steps lol next stop high pressure fuel pumps and the benefeit without a turbo, haha i hate to change threads!

 

hey whats up im not familiar with turbo audis but one thing im familiar with is turbo cars. i had a 1989 Dodge daytona turbo2 intercooled with a stock garrett t03 and all of us turbo dodge guys always when with a 3" straight pipe no cat that whent out the side of the car infront of the rear tire. All the turbo daytonas with that exhaust set up were pretty quiet because the turbo absorbes most of the sound.

and as far as smaller pipe making a turbo spool faster is not true. plus turbo cars dont need back pressure infact the less back pressure you have the better and that doest just apply to the turbo dodge cars it applys to every turbo car.

i dont know how audis work but i dont see why it would be different