Catback VS Turbo-Back Exhaust

[talkinghamster]

Hey all, just wondering is it worth it going turbo back or is cat back good enough??

dont want that ricey 4 banger sound, just after performance not sound.

also plan on doing big turbo swap... waiting for unitronic to announce a kit.

thanks all

[sfl_A4]

On turbo motors minimizing exhaust back pressure is generally accepted as essential for improved power. With a 2 liter displacement, 3" piping from turbo back into dual 2.5" seems to be work quite well from tests I've read about. That shouldn't be too loud during normal driving, and you will likely experience a nice little growl at WOT.

[mlavelle92]

Turbo back on the 2.0T, need to reduce as much back pressure as possible, especially right up against the turbo (cat). Change the exhaust won't really do much if you leave your cat and downpipes untouched. Different case than the N/A engines

[tdowns7529]

95% of the gains in an aftermarket exhaust on a 2.0T is due to a HFC. Really relieves the back pressure by the turbo. I just put one on (034) keeping the stock exhaust and had impressive performance gains (along with APR Stage 2 version 2. And despite my fears, no tin can, drone, or ricey sounds. Just a little more throaty. I heard that is the case more so for the B8's. No idea why, but it was in my case.

[talkinghamster]

95% of the gains in an aftermarket exhaust on a 2.0T is due to a HFC. Really relieves the back pressure by the turbo. I just put one on (034) keeping the stock exhaust and had impressive performance gains (along with APR Stage 2 version 2. And despite my fears, no tin can, drone, or ricey sounds. Just a little more throaty. I heard that is the case more so for the B8's. No idea why, but it was in my case.

have been doing some reading and this is what i have found as well!!

plan on doing this. but i want that dual exhaust look. oh why do things have to cost money lol

[034Motorsport]

95% of the gains in an aftermarket exhaust on a 2.0T is due to a HFC. Really relieves the back pressure by the turbo. I just put one on (034) keeping the stock exhaust and had impressive performance gains (along with APR Stage 2 version 2. And despite my fears, no tin can, drone, or ricey sounds. Just a little more throaty. I heard that is the case more so for the B8's. No idea why, but it was in my case.

This is correct; most of the gains from exhaust upgrades on the 2.0T are made by replacing the restrictive factory catalytic converter. Here is a back-to-back dyno of my B7 from when we were developing our 034Motorsport B7 Audi A4 2.0T FSI HFC many years ago:



Cheers,
Laszlo

[Seerlah]

You size things accordingly and mod appropriate to your mods. Stock cat is very restrictive, and why gains are so noticeable on the stock turbo with a TP or HFC. If running a larger turbocharger, then you ideally want a less restrictive cat (100-200 cell) if still wanting to run one, or no cat at all. For example, I ran a HFC with upgraded exhaust when I was stage one with bolt ons. But now that I have a larger turbocharger, I run no cat and actually need to up the size of my exhaust system (current downpipe size is a huge restriction at 2.5").