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Old 26 Jul 2010, 09:18 PM   #1 (permalink)
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Dump valve

Right, you've all had this questonbefore but I just wanna ask it again, think i know answer lol I got a my99 uk turbo 2000, standard apart from decat and walbro at the moment. gonna fit td05 and remap later, but in meantime i wanna play about, i want that dump valve woosh. Is it safe for me to put a atmos on instead of recirc on this 'standard' car? I know I'll need to block off certain pipes etc, but can I get away with a baileys piston for example?
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Old 26 Jul 2010, 10:02 PM   #2 (permalink)
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Re: Dump valve

bov can cause the car to run rich as the ecu still sees the air as being in the manifold. Bailey dump valvs are prone to leaking. I would stick with the standard one
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Old 27 Jul 2010, 08:08 PM   #3 (permalink)
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Re: Dump valve

If you use a vta (vent to air) valve, when it opens the car will over-fuel. It's already metered the air you just vented away so puts fuel in for it and will run rich. Over a long period this will foul the cats if you have them. If you don't you can get pops and the odd flame out of the exhaust. You won't get any performance gain as the standard dump valve works perfectly fine. It's all down to whether you like the noise or not and whether or not you want to risk damaging the car or it running like a bag of s**t
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Old 27 Jul 2010, 08:11 PM   #4 (permalink)
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Re: Dump valve

Well thats pissedon my corn flakes lol cheers fellas
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Old 27 Jul 2010, 08:20 PM   #5 (permalink)
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Re: Dump valve

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Originally Posted by martinarnold_1uk View Post
Well thats pissedon my corn flakes lol cheers fellas
if I really really wanted a dv think I'd go safe and get the Forge 50/50. Vents half the metered air and the other half recircs
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Old 27 Jul 2010, 08:34 PM   #6 (permalink)
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Re: Dump valve

Which forge is that please? Is that th unit that looks pretty much like the standard one? I assumed being recirc it would't make any noise?
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Old 27 Jul 2010, 08:52 PM   #7 (permalink)
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Re: Dump valve

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Originally Posted by martinarnold_1uk View Post
Which forge is that please? Is that th unit that looks pretty much like the standard one? I assumed being recirc it would't make any noise?
Forge Motorsport | Alloy Fabrication
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Old 27 Jul 2010, 08:59 PM   #8 (permalink)
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Re: Dump valve

Sorry to sound thick, but u got a pic? All ones ive found say dont make ANY noise
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Old 27 Jul 2010, 09:11 PM   #9 (permalink)
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Re: Dump valve

There's a picture on the link above. You'll need a fitting kit with that one there not a bolt onto the intercooler job. There called a splitter valve
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Old 28 Jul 2010, 06:41 AM   #10 (permalink)
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Re: Dump valve

Cheers fella, looks just the job
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Old 28 Jul 2010, 05:46 PM   #11 (permalink)
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Re: Dump valve

ive a dump valve on mine (2001) wrx and it runs sweet as, it can cause problems though. If you have car mapped then they can make sure it wont do damage as they map the car to its mods etc, one thing though if its a 99 uk spec 2000 turbo its not mappable and you need aftermarket ecu.
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Old 28 Jul 2010, 10:22 PM   #12 (permalink)
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Re: Dump valve

The forge 50 /50 offers no advantage over a std recir,or a normal vta bov,as it is neither one or the other. A decent bov like a blitz,will vent to atmosphere when your hitting decent revs,and remain quite quiet at low revs Baileys have 2 springs and are prone to weak springs and can cause erratic idling.A lot of people prefer the std recirc valve which is good for 350+ bhp
Also the 99 uk spec is mappable as i had bob rawle do my 99 uk turbo and my 2000 uk turbo- both ecu tec so with licence can be mapped. It is the 96 -98 ecu's which need the aftermarket board ,but not for to long as a chip is being devised for these ecu's.
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Old 28 Jul 2010, 10:55 PM   #13 (permalink)
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Re: Dump valve

i have a bailey one on at the minute, luckily it seems ok at present but i will be replacing it with a decent one in the future,it was on when i bought the car a few month ago so not replaced as yet
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Old 19 Feb 2011, 02:13 PM   #14 (permalink)
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Re: Dump valve

hi shambles just a quick question does the dump valve spring on a forester 2.0xt have the same spring setting as an impreza my2000 turbo uk having a few issues with my impreza it has good boost ( on gauge anyway ) 13psi but doesnt give that scooby kick when you throttle up any suggestions will be very welcome its doing my head in !!!!
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Old 19 Feb 2011, 03:45 PM   #15 (permalink)
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Re: Dump valve

Not sure about the forester dump valve
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