Neuspeed 2.5" cat-back exhaust has been on the 1.8T for about 1 week, with stock K03 turbo and GIAC X chip. I notice at WOT that there is a loud pshhhhhhht! noise coming from the front right, which I suppose is either the intake sucking in air or a leak of some kind. Neither explanation makes a lot of sense to me. It's the stock intake and I've never heard of people's stock airbox making an impressive whooshing noise with just a cat-back exhaust. On the other hand the car seems to be pulling fine so a boost leak isn't very plausible. (Sadly, I do not have a boost gauge.) Is this just normal operation or should I be concerned?





And in the vain hope that somebody might do a search for exhaust + impressions here are mine:

It stank at first like something burning. Searching Audiworld archives lead to comments that this is lubricant in the exhaust burning off and it would go away, and sure enough the smell has gone away.

It's pretty ... loud. When my wife is in the car I probably get better mileage now because I think she'd be appalled at the noise, so I try to tame the lead foot. While some people with Borla exhausts have proclaimed their love for the sound of the Borla, I'd say I am getting used to the sound of my Neuspeed.

It does seem to pull a little harder and spool a little easier but it is a subtle change. Car has never been dynoed, so I couldn't say anything about HP and torque numbers.

the DV may be wearing out, added to the fact that you have an X chip, exhaust, and the noise is isolated to WOT, it could all add up to a leak. If you want to check the exhaust for a leak, get under there when it's cold, have someone start it up, and eiter spray the DP flange with some soapy water and check for bubbles, or feel your hand up around it for air spitting out. The whole area will get get warm fairly quick, so do it fast. Also, make sure that the sound you are hearing is in fact a hiss sound and not a whine sound. If it's a whine, then it's just the turbo spooling, but it sounds like you already knew that. Anyway, if it's the DV leaking, go shopping for an aftermarket one. I have my eyes set on a Forge 007, but most of the billets out there are good quality. Good luck.