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dump valve idiots question

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Old Jul 7, 2002 | 01:29 PM
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Excuse my total lack of knowledge!

So my car has a dump valve already(I assume) MY01 WRX.

If I slap a forge dump valve on, what will this do for me???? and how noisy are they?? any performance gains? whats the point??

thanks

Andy
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Old Jul 7, 2002 | 01:48 PM
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Andy

You are correct, your car has a recirculating dump valve as standard which puts the air back into the system.

There have been many arguments/debates about whether there is actually any benefit to fitting a Vent to Air such as the Forge item or not. Some tuners swear by them some don't like them. Some people fit them because they have decat exhausts and this helps to produce flames from the unbunt fuel in the exhaust.

I have a MY01 WRX PPP and recently fited one to my car. Since fiting it, although outright performance hasn't increased the turbo spool up occurs a lot quicker. So the initial response has improved. AFAIK This is because the turbo can spin up in free air. The noise from the Forge VTA is nice, its not too loud but you can hear it quite clearly.

Sorry this isn't a technical explanation, but hey at least I tried If your unsure why not pop along to a local meet, I'm sure someone would take you out so you could see for yourself.

Nathan..




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Old Jul 7, 2002 | 03:22 PM
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Thanks Nathan, your reply was exactly the kind I was after!

It seems maybe Id be better off getting ppp or full decat then, Im on a mini mission to make it just a bit quicker

andy
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Old Jul 7, 2002 | 03:38 PM
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Faster spin up when hammering through the gears, a noticeable improvement, regardless of what the non believers say.
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Old Jul 7, 2002 | 03:39 PM
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If you want to keep your warranty then the PPP is a sensible route. Power around 245 bhp

Otherwise there are better options. Most of which kill yur warranty, just the decat on its own shouldn't kill all your warranty though.

A full decat + Good air filter should be good for 255-260 BHP.

Full Decat + PPP should be good for 275-285 BHP.

Full Decat + Link ECU or Motec ECU should be good for 300 +

Mail me off line if you want for any more pointers.

Nathan..


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Old Jul 7, 2002 | 03:41 PM
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Brun I would have to agree with you there mate.

Nice bit of flame when gunning it too

Nathan..
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Old Jul 7, 2002 | 04:37 PM
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Brun & Nathan,

Engine tuning isn't about belief, it's about engineering.

Read this classic on dumpvalves

http://www.scoobynet.co.uk/bbs/threa...ThreadID=28135



If your car feels quicker, (and let's suppose it is), it only means your aftermarket dumpvalve dumps less air / dumps it slower / dumps later, thus effectively reducing turbo protection, especially on a TD04L

I really really wonder when this "turbo spools up more easily" con will disappear.

Dumpvalves are about turbo protection, not power. A car without a dumpvalve will be QUICKER through the gears (assuming you can shift quickly enough to take advantage from the pressure that stays on tap) than the same car with a dumpvalve (anodized blue or not).

A "non-believer", mainly because this is ... erm ... fact.
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Old Jul 7, 2002 | 04:57 PM
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EvilBevel
Try reading mine and Nathans posts a little closer, neither of us have mentioned performance gains. All i'm saying is that when booting it through the gears, boost is there for the taking instantly, where as with the OE item it wasn't. I don't really care about the technical bumph behind it all, all i know is my car feels better to drive with my Forge. I'm sorry if you don't like our opinion, but you will find many more people with the same opinion, and with respect, there is probably the same amount of people who share your opinion. So if your happy we'll call it a draw.
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Old Jul 7, 2002 | 05:01 PM
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Edited cos I can't be bothered to argue swith someone who resorts to insults anymore.

[Edited by Nathan L - 7/7/2002 5:06:47 PM]
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Old Jul 7, 2002 | 05:02 PM
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Not talking opinion. Talking facts.

Your car is slower through the gears with a well performing dumpvalve. Fact.

If you feel an improvement with a Forge/whatever, it means your dumpvalve is not doing it's main job: protecting the turbo/ throwing away all the pressure during the gearchange.

I don't exactly think I need reading lessons from you. I think you OTOH need to be careful with giving advice... especially as it is wrong.

Have you tried blocking off your dumpvalve or haven't you ?

So not even close to a draw ... more a 5-0

Theo

PS: you are a fast reader... did you really digest the link I gave you ?
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Old Jul 7, 2002 | 05:03 PM
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"They don't fit a recirculating valve to the WRC do they?"
OK, here is your trick question for the day ... but do they fit a dump to atmosphere one ?

LOL

Hope you don't trust that tuner too much then
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Old Jul 7, 2002 | 05:09 PM
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I've removed my entire last post because you are more interested in getting a rise than actually debating something.

You obviously read far too much and just believe it.

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Old Jul 7, 2002 | 05:11 PM
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You stick to your facts, and again if you read my post a little closer, you will struggle to find any advice, only an opinion offered.
If opinions are not allowed on here, i offer an apology to everyone involved with this thread.
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Old Jul 7, 2002 | 05:34 PM
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Edited cos I can't be bothered to argue swith someone who resorts to insults anymore.
Erm... where exactly did you read any insults ? Can you specifically quote one ?

You removed your statement because it was so wrong it was funny, almost painful. I'm glad I quoted it fully though. Can we have the name of this "well established tuner" who you quoted ? Gives us another name to avoid like the plague.

Yeah I agree getting a rise out of debunking wrong information, even if afterwards deleted or stated "but it is an opinion blah blah".

Sure you can state any opinion you like, even "the earth is flat". It may be pointed out however that it is a bit wrong-ish, but don't attack the messenger in that case. And certainly don't attack any people pre-emptively about being "non-believers".

Hope you learned something from all this.
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Old Jul 7, 2002 | 05:36 PM
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You obviously read far too much and just believe it.
OK, so I challenge you (am in a bad mood now) : do WRC cars have dumpvalves ?

Simple yes or no is enough.

May I also kindly point out I probably read more & believe less, especially marketing crap ?

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Old Jul 7, 2002 | 06:33 PM
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From: Fcon Power Writer
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.
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