VW Vortex - Volkswagen Forum banner
1 - 20 of 32 Posts

·
Registered
Joined
·
217 Posts
Discussion Starter · #1 ·
I have just finished installing my Eurosport DP and after taking it out, I noticed a sort of hissing sound, not a whistle or a whine like the CAI added, but more of a smooth exhaust hiss. I have inspected the flange where it meets the turbo, and it's not leaking, and the sleeve clamp is good too. Is this just normal for the DP's because of the thinner wall tubing and less restriction?
Eric


[Modified by 2003Jetta1.8t, 11:18 PM 1-22-2003]
 

·
Registered
Joined
·
9,909 Posts
Re: Hissing sound with Eurosport DP?!? Answer please.... (2003Jetta1.8t)

Sounds normal to me. I don't have any experience with the Eurosport system, but I know others that make a distinctive 'hiss' when under full boost.
 

·
Registered
Joined
·
217 Posts
Discussion Starter · #5 ·
Re: Hissing sound with Eurosport DP?!? Answer please.... (FlyinTurbo)

Well, I went out to the garage and pulled the downpipe off of the turbo....I fully inspected the gasket and it shows NO signs of any carbon deposits except around the inside if the sealing surface. There were no signs of any carbon around the steel ring, nor any sign of exhaust discoloring the 'paper' part of it. Reassembled it, and still same noise at full throttle....Its not loud, just sounds like a hiss. I wonder if it is the sound of the wastegate bypassing exhaust pass the compressor and the pulses are causing the slight hiss....Glad to know that its normal though...

[Modified by 2003Jetta1.8t, 10:28 PM 1-22-2003]


[Modified by 2003Jetta1.8t, 11:19 PM 1-22-2003]
 

·
Registered
Joined
·
217 Posts
Discussion Starter · #7 ·
Re: Hissing sound with Eurosport DP?!? Answer please.... (Boostin20v)

Yeah, it only does it at full throttle under boost at high rpm 4000 and up. I have had my fiance sit in the car and rev it up to 6000 as I felt around the flange from the turbo to the DP and I felt no leaks at all. I guess I'll just have to get used to the sound, it dosent become apparent until you really get on it anyay. The DP did add TONS of torque and it was well worth the $!
 

·
Registered
Joined
·
3,116 Posts
Re: Hissing sound with Eurosport DP?!? Answer please.... (2003Jetta1.8t)

quote:[HR][/HR]Yeah, it only does it at full throttle under boost at high rpm 4000 and up. I have had my fiance sit in the car and rev it up to 6000 as I felt around the flange from the turbo to the DP and I felt no leaks at all. I guess I'll just have to get used to the sound, it dosent become apparent until you really get on it anyay. The DP did add TONS of torque and it was well worth the $![HR][/HR]​
glad to hear you like the dp, i will e-mail eurosport & the pottermans to see if they can figure out what it is
 

·
Registered
Joined
·
3,116 Posts
Re: Hissing sound with Eurosport DP?!? Answer please.... (gti_jeremy)

quote:[HR][/HR]a little sound at wot past 4000 rpms cant hurt right? why be quiet during those situations.[HR][/HR]​
true enough - i know some people have gotten sounds with a 3", havent heard too many 2.5" dps
 

·
Registered
Joined
·
217 Posts
Discussion Starter · #12 ·
Re: Hissing sound with Eurosport DP?!? Answer please.... (2003Jetta1.8t)

BTW I even VAG'ed the thing and it isn't showing any DTC's as an exhaust leak will under part throttle when there is being outside air sucked into the exhaust stream befure it gets to the O2's. Everything checked out ok with it.
Eric
 

·
Registered
Joined
·
1,686 Posts
Re: Hissing sound with Eurosport DP?!? Answer please.... (Tornado20v)

I noticed this type of sound when I first chipped.
I think it is just the sound of increased exhaust flow through the pipe.
 

·
Registered
Joined
·
2,880 Posts
Re: Hissing sound with Eurosport DP?!? Answer please.... (slugII)

You are hearing your turbo. Plain and simple

Reason is because it is breathing better... A whole lot better hence the reason for the downpipe. Drive like you stole it and enjoy
 

·
Registered
Joined
·
2 Posts
Re: Hissing sound with Eurosport DP?!? Answer please.... (RonN)

Did you make sure you used a new gasket, sound like an exhaust leak to me. I had a header crack on me and that was the sound it made, a hissing soind right.
Next time you in you car, hang you head out of the door and listen to the exhaust under car while you rev it, slowly increase you revs. Thats should be the problem, take it form a pro.
-deez
 

·
Registered
Joined
·
217 Posts
Discussion Starter · #17 ·
Re: Hissing sound with Eurosport DP?!? Answer please.... (deeznutzz)

deez, read my previous post about actually being under the car while my fiance revved it to 6K while my hand was 1/4" away from the flange....No leak..BTW I am no n00b to cars...


[Modified by 2003Jetta1.8t, 10:10 AM 1-23-2003]
 

·
Banned
Joined
·
1,665 Posts
Re: Hissing sound with Eurosport DP?!? Answer please.... (2003Jetta1.8t)

I bet my hard earned dollar what your hearing is the Turbo? IN fact I know thats what you are hearing. Gotta remember that thing is really whirling around in there now! Did you compare the to DP's prior to install?? The Eurosport is like a keg compared to that little nip that was previously on there! That sound is the turbo boosting like a mad man!
Its a high pitched sound yea? You just free'd up the most restrictive part of the exhaust and its loving it.
Ooh yea, did I mention. I have the Eurosport DP as well. couple thousand miles or so. Got the same sound. I think any DP would do the same. But Eurosport was a high quality GB that I couldnt pass up! 305 bux! dizzzzam. Good luck!
 

·
Registered
Joined
·
217 Posts
Discussion Starter · #19 ·
Re: Hissing sound with Eurosport DP?!? Answer please.... (CruisVW)

Its not really a high pitched sound....More like a flutter...But not a tick....
Anyway, just talked to Eurosport and they said that it is a normal sound, and it is most likely caused by the wastegate actuation during full throttle. They said since the tubing diameter is much larger than stock, it can cause a resonance when the wastegate flap opens (remember it is at an angle when open) and directs the excess exhaust pulses towards the wall of the pipe. This sound flucuates with the wastegate actuation, because it changes noise level with boost spikes, as the compressor tries to slow itself down and limit boost. When it does this, it opens the wastegate flap further, allowing a greater amount of the bypass exhaust out of the flap and then it is directed into the pipe wall. As soon as the spike disappears, the sound changes level (even though RPMs have been climbing all along) as the wastegate has closed some trying to keep boost at the ECU requested level. From what I understand, the wastegate is open partway under WOT in the upper RPM's anyway because the K03 sports can flow more at higher RPM's, so they need the wastegate to limit boost (It may be this way for regular k03's too). This sound is only in the upper RPM's because the wastegate is closed at lower RPM's to direct all of the exhaust flow through the compressor to spool the turbo up quickly (to meet requested boost), and the exhaust flow of the engine has not reached a point at which it will overspool the turbo. As engine speed builds, then the wastegate gradually opens to limit boost (you all ready knew that, I know). Hence the changing pulse/hiss with requested boost from the ECU. Eurosport stated that their own cars make this noise, and that it is there on most cars, although some dont seem to do it. Some people must just interpet the sound as increased exhaust flow, when it is actually a resonance, mixed with wastegate actuation and the wastegate flap directing the exhaust pulses towards the wall of the pipe.
The sound actually reminds me of putting long tube headers on my Stang and, I could hear the exhaust pulses louder when I got on it, because of the larger tubing and the resonance in the pipe, vs. the stock cast 'log' headers which dampen sound.....The VW stock DP seems to have its flange and reducer made of thick walled tubing, and the whole thing may be double walled...Can anyone confirm this?
Eric
Sorry so long, just thinking out loud

Eric
 

·
Banned
Joined
·
1,305 Posts
Re: Hissing sound with Eurosport DP?!? Answer please.... (2003Jetta1.8t)

quote:[HR][/HR]Anyway, just talked to Eurosport and they said that it is a normal sound, and it is most likely caused by the wastegate actuation during full throttle. They said since the tubing diameter is much larger than stock, it can cause a resonance when the wastegate flap opens (remember it is at an angle when open) and directs the excess exhaust pulses towards the wall of the pipe. [HR][/HR]​
Thats what it is, you should her a longitudinal car with a larger DP, and even then it still had to go through the same cat, but man those things get loud.
 
1 - 20 of 32 Posts
Top