Spec me a Dump Valve

Bear · 12 Dec 2006 at 13:28

Entai said:
If you mean the S13 engine fitted to Nissan 200SX's etc then sorry but they came as standard from the factory with a recircuating valve as standard factory fit, or so the FAQ's say at 200SX.org!!
See here, click on Enhacements in the menu on the left then look under the explanation for "BOV" - Blow Off Valve.

No they didnt s13s dont have a recirc fitted as standard. The s14s did though.

Phate · 12 Dec 2006 at 13:29

agw_01 said:
Are you sure you guys aren't hearing the fake dump valves on all these little chav shopping trolleys?

I saw a black modded Corsa trying to follow an Evo once. The Evo went past and dumped... the Corsa went past and farted

lol

they probably are fake

but it's all a laugh at the end of the day.

EddScott · 12 Dec 2006 at 13:59

agw_01 said:
I'm seriously shocked at how the hell dump valves have been assigned a 'chav' link.

Go on Scoobynet and ask what atmos DV should be fitted to an Impreza.

The opinion on SNet is that these things are equal to burberry caps and trackie bottoms tucked into your socks.

I took mine off for two reasons - 1, it wouldn't fit the larger intercooler I fitted and 2, I wanted to see if it made a difference in the way the car went.

It made a difference for the better so I decided not to buy another atmos DV.

I also couldn't stand my 5" exhaust although I loved the look of it sticking out at an angle from under the rear of the car. Bought a much quieter Grp N box and there has been no difference to performance.

I now realise you don't need all these noises to make a fast car.

Stonedofmoo · 12 Dec 2006 at 14:34

Phate said:
Is there a technical reason for this? or simply the fact that you don't like them?

if people tell me not to go for it I want a technical reason to it

not just the fact that chavs have them.

Yes, the T7 will not be aware the air is now being lost to the atmosphere, as a result the air/fuel mix it provides will be wrong
This is why you can look on any Saab tuning site and you will NOT see an atmospheric dump valve for modern Saab's

If you want to mess up your engine for the noise then go ahead, but Saab engines are sophisticated and need to be setup correctly.

Stonedofmoo · 12 Dec 2006 at 14:41

Yeah I had a dump valve on my Pulsar. It was a tuned car that would make a hissing noise even with the standard recirculating dump valve
I had a spring that stopped it hissing unless you were really going for it

IMO dump valves are fine on a proper performance car.

Dump valves on your Saab, Audi etc etc etc are just lame and purely on there for the noise. If you want the performance noise a DV provides get a performance car!

IceAx · 12 Dec 2006 at 15:26

Psycrow said:
He bought a saab turbo. No idea about what dump valve but it will be funny seeing an old saab drive past then pppssssssstttt.

Almost as funny as my smart comming past pssssssst

Andy

EddScott · 12 Dec 2006 at 16:10

Stonedofmoo said:
Yes, the T7 will not be aware the air is now being lost to the atmosphere, as a result the air/fuel mix it provides will be wrong
This is why you can look on any Saab tuning site and you will NOT see an atmospheric dump valve for modern Saab's

If you want to mess up your engine for the noise then go ahead, but Saab engines are sophisticated and need to be setup correctly.

But then is that not the same with any car?

The air/fuel goes out the window if DVs are fitted. Mine used to make some loud pops and bangs off the gas but this was down to the DV and overfueling. I did like that I must say but the benefits of a smoother running car outway that.

I had a SSQV on my GTIR and it didn't feel any different when I took it off. Not like the difference I felt when taking the SSQV of my Impreza.

Phate: if your really going to do it, just buy a cheap bailey one and some hose. Connect it all up and see what happens. If it works fine, if not take it off. Simple as.

Axeboy · 12 Dec 2006 at 16:15

never had any issues with vta's on my car...

As said above, try and see

Hate · 12 Dec 2006 at 16:21

EddScott said:
But then is that not the same with any car?

the celica uses a MAP, so I can dump all i like.

eztiger · 12 Dec 2006 at 16:21

My Mitsi GTO has had its stock recirc valve replaced with an atmospheric one. (Blitz)

This was before I bought, but to be honest apart from the extra petrol usage (which, as it feels like its urinating petrol out the exhaust anyway in the amount of money you spend at the pumps, isn't a big deal) theres no noticeable performance problems driving.

I love it, great fun roaring up through the gears.

Apart from vanity / comedy purposes, the stock GTO recirc valve suffered badly from corrosion / rot so the aftermarket ones are actually a recomended upgrade.

It probably would seem a bit daft on a corsa though

What *is* chav is the stupid HKS super drager exhaust someone stuck on it. I could fit my head up the exhaust exit. Sounds like an earthquake everytime you start it

Kev

panthro · 12 Dec 2006 at 16:42

I drive my car 99% of the time off boost around town so no one can really hear the dump valve. I dont think it sounds silly, but I could live without the sound.

R220 · 12 Dec 2006 at 17:49

I have a atmospheric dv, but even with the recirc valve on you get a fairly loud psst sound. Might go back to recirc soon as the louder pssst that the atmospheric valve gives does my head in after a while.

Stonedofmoo · 12 Dec 2006 at 17:54

Do you own a modern 9-3 or an old one?

What year is it?

If it's 98 or later it will have the Trionic 7 engine management and fitting an atmospheric dump valve will cause the engine management lights to flick on like a christmas tree soon as you change gear

But if its an older model with a Trionic 5 ECU I believe you can get away with it as these are not as sophisticated.

Dandle · 12 Dec 2006 at 18:26

Stonedofmoo said:
Do you own a modern 9-3 or an old one?

What year is it?

If it's 98 or later it will have the Trionic 7 engine management and fitting an atmospheric dump valve will cause the engine management lights to flick on like a christmas tree soon as you change gear

But if its an older model with a Trionic 5 ECU I believe you can get away with it as these are not as sophisticated.

I didnt think the 9-3 came out until 98, I could be wrong though.

The_Dark_Side · 12 Dec 2006 at 18:41

agw_01 said:
Not having a go or anything, just interested as to why people think DV's are silly.

IMHO it's the mechanical equivalent of windows down+stereo up full blast...or dropping the soft top and shouting "EVERYBODY LOOK AT MEEE"