I realise this may be controversial but I'd like my S4 to woosh

S4UTTLEY

S4UTTLEY

S4 B5
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I don't want to start a mass argument about this about dump valves are for chavs ect lol I am a chav and I want my audi to have the noise when I lift off change year ect can I do this without damaging ect , I had a bora 1.8t be for and I put a filter on and it did it straight away ? Please help ;) b5 s4
 
Just put a open filter on or mod the air box below the filer and stick some 710n DV's or forge 007p's/008's.
 
Lmao you certainly speak like a chav even through forum!

If you want a dump valve get a forge diverter valve for your S4 that will give you the noise.
 
Some explanation required i think.

The ECU on the S4 (and many other modern cars) measures the amount of air flowing thru a sensor (the MAF) and uses this value to calculate fuelling.

If you have an airleak, say a split pipe or burst hose, air passes thru the MAF, but never makes it to the engine, which results in the car running like a sack of ****, as the amount of fuel being injected doesnt match the amount of air thats present in the cylinders.

So how does that apply to dump valves? Well, as standard the dump valve simply recirculates the air from the pressure side to the intake side of the turbo. This means that no air is lost, and the MAF readings stay correct and the ECU stays happy. However when you install a atmospheric dumpvalve (the ones the make the loud tishing noise) they work very specifically by creating a huge air leak, dumping all that boost out into the engine bay. So this causes the engine to run like ****e.

As you found with the Bora, replacing the standard airbox with an open cone will allow you to hear more easily the standard recirculating valve doing its job. However on the S4 theres many more miles of intake pipework, and you might find that even with an open filter you wont hear much!
 
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What Aragorn says.

BUT if you REALLY want the pSSSSH sound without causing your car to run badly, believe it or not you can actually buy "fake" dumpvalves (!). It's basically an electronic device. Think it connects to the accelerator, so when you lift off and the throttle closes, it triggers a sounder under the bonnet to release the hiss.They came out after the first Fast and Furious film so people could put them on non turbo cars (haha)

Or you could just try what effect it would have on the car, disconnect the return feeds to the diverter valves you have on already, plug the return hoses with a metal or plastic bung that's gripped by the jubilee clip so it won't fall out and go for a quick drive. Your OEM valves will vent to atmosphere and you'll get the noise and also see what effect it has on how the car runs. If it's ok, and you are happy, go buy some VTA dumpvalves. But be prepared for possible issues later.
 
Whilst all the above is correct I've been running an HKS SQV atmospheric DV for a couple of years now with no ill effects. The car does have an idle issue where the revs drop but the DV has been totally ruled out as being in any way responsible. In fact nobody has been able to offer an explanation to the issue despite a few diagnosis being offered, including the MAF, which proved an expensive miss diagnosis.
 
Some folk seem to get away with it.

Essentially you get a rich spike after any gearchanges, and when declutching. I guess depending on various factors this spike might do very little, or it might upset the engine enough to cause it to bog down/flatspot/etc.

Theres also certain DV types/designs which will open at idle and stay open due to the vacuum being applied, clearly these are totally unsuitable, as they create a leak all the time.
 
Yep, if I dip the clutch and coast the revs just keep bouncing between 500 to 1000rpm. Soon as I come. To a standstill it ticks over fine. Was fine until the battery went flat. No fault codes, gone through everything I can think of and still the same.
 
IIRC i did a throttle body alignment and changed the idle speed setting and it seems to have cured mine. Will double check tomorrow and see as havent noticed it recently and cant think if i changed anything else before it stopped doing it !!
 
audi upgrades
Checked this morning and it doesnt do it anymore so give the idle adaptation and throttle body alignment ago, if i get chance weekend i will see what ive set mine too and let you no.
 
Oranoco said:
I haven't tried that, will take a look. Where will I find it? Any test I can do?
Click to expand...

Just remove the piping to tip and manifold and plug them. Thats all i did must off been that whats was causing it as i only did it recently. Leave it plugged in an just venting to atmosphere.

edit: its the black thing in the pic with the 'F' hose coming off it.

 
Yeh thats the fella.

On mine, i blanked the manifold pipe, blanked the TIP connection, and disconnected the pipe that goes into the wing and tucked it out the way (but left it open, so the tank can vent itself)

Leave the valve itself plugged in, or the ECU gets annoyed.

Also means you can tidy up the bay a little by removing some of the messy pipework!
 
Here is how mine looks at the minute no pipe at tip and no pipe going across firewall to manifold.

 
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aragorn said:
Some explanation required i think.

The ECU on the S4 (and many other modern cars) measures the amount of air flowing thru a sensor (the MAF) and uses this value to calculate fuelling.

If you have an airleak, say a split pipe or burst hose, air passes thru the MAF, but never makes it to the engine, which results in the car running like a sack of ****, as the amount of fuel being injected doesnt match the amount of air thats present in the cylinders.

So how does that apply to dump valves? Well, as standard the dump valve simply recirculates the air from the pressure side to the intake side of the turbo. This means that no air is lost, and the MAF readings stay correct and the ECU stays happy. However when you install a atmospheric dumpvalve (the ones the make the loud tishing noise) they work very specifically by creating a huge air leak, dumping all that boost out into the engine bay. So this causes the engine to run like ****e.

As you found with the Bora, replacing the standard airbox with an open cone will allow you to hear more easily the standard recirculating valve doing its job. However on the S4 theres many more miles of intake pipework, and you might find that even with an open filter you wont hear much!
Click to expand...

Sorry to interject here, but just wondering how things like scoobies have such a loud hiss then - is there some sort of sacrifice to achieve this (surely not?)
 
Scooby turbos have stronger shafts than the borg warners on the s4 so can withstand being stalled if they are going all out. And the management is crap so doesn't care if the air is missing due to the ecu being a bit stupid
 
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Perhaps they dont use a MAF?

Or maybe they're just less sensitive?

Or maybe they are just as sensitive and the chavs put up with it for the loud noise?
 
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Interestingly, having a quick look on scoobynet finds similar discussions to here. IE dont do it because the management doesnt like it and it makes the engine run rich.

So i guess its just ignorance, or luck, much the same as the folk who fit them to VAG's!
 
The ecu on the earlier cars is sucky. They piggy back to control everything with add ons . One for fuel, one for boost etc
 
Ah right I see, cheers lads, useful lesson! To be honest I'm not sure I've ever seen a scooby that didn't scream lol, so I assumed they were as such straight off the line!
 
I had a scooby a few years back I just blanked the DV off and it made a awsome chatter ran it like that for years no problem ;)
 
Scoobies do have recirculating valves as standard and lots of people do fit VTA dumpvalves and get away with it as the engine management is very basic. I had one fitted to my 400bhp Impreza for about 5 years and it didn't cause any issues at all, although I do know of people fitting cheap ones that had idling issues cos the things didn't seal properly.

With a full decat exhaust (like I had) you also used to get louds pops in the exhaust (when hot) after most gearchanges from the unburnt extra fuel going bang from it running momentarily rich. Not good if you've got a cat tho. Can't do it much good.
 
Idle Speed Adaptation:

With engine warmed up, at idle:

[Select]
[01 engine]
[Adaptation - 10]
Enter channel 01
Enter an adaptation value between 124 and 132
[Save]

(May require a Login of 01283 or 11463, depending on year or model)
 
i had a dump valve fitted on my a4 until the time it came to MOT and i found the cat had been ruined by unburnt fuel flying through it cos the air in the system had been vented.. one brand new cat later the dump valve got binned...

fitted a Revo sponge cone filter and an enclosure and you still get a whoosh with that...
 
B5QUAT said:
What Aragorn says.

BUT if you REALLY want the pSSSSH sound without causing your car to run badly, believe it or not you can actually buy "fake" dumpvalves (!). It's basically an electronic device. Think it connects to the accelerator, so when you lift off and the throttle closes, it triggers a sounder under the bonnet to release the hiss.They came out after the first Fast and Furious film so people could put them on non turbo cars (haha)
Click to expand...

this is the stupidest £$"£$ing thing ive ever heard of.
 
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