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Discussion Starter · #1 ·
What do you think is the best dump Valve for the 1.8 T? Diaphram? Piston? Twin Piston? Re-Circulating? what have you? ..........

What outways Performance, Looks or Price.......
 

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It depends on which 1.8T engine you have,
if it's the early engine (AGU) then fit which valve you want, atmospheric or recirculating.
If it's the later engine (AUM) then you must fit a recirculating type as the MAF sensor throws a wobbler
when the air is dumped to atmosphere.
 

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sorry to hijack your thread...

this is a silly question....can a dump valve increase the power of your car or is it to make it sound better?
 

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Discussion Starter · #5 ·
I keep hearing stories that the Re-circ ones are better for VW engines? Can anyone confirm this?
 

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I keep hearing stories that the Re-circ ones are better for VW engines? Can anyone confirm this?
that appears to be the case i have been researching post about DV's for ages and apparently BOV's can knacker your MAFso i finaly decided to get a forge recirc one, better safe than sorry i already get that sound from my carbonio so there is no need to get a BOV,
Dump Valves can reduce turbo lag buy upto 20% i hear so they are worth while having. and if you remap your car the old standard bosh one will just pack up.
Thats all i know about the matter.
 

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The standard Bosch one has been much criticised but is still the fastest reacting one out there!  It also has the benefit of being cheap to replace.  In addition, the current ones aren't damaged by higher boost levels like the earlier ones though the rubber will probably split eventually. They are about ?30 a time so you can work out how many you'd have to go through to get to the cost of a Forge one.  Needless to say my piston DV is packed away somewhere and I've been running a Bosch one quite happily since last summer.  Just my 2p, others swear by the Forge ones.
 

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I keep hearing stories that the Re-circ ones are better for VW engines? Can anyone confirm this?
Yes, that is correct!

Dump valves are meant for "dumping" excess pressure into the atmosphere, hence the term atmospheric. Thats where the whoosing sound comes from. VW's, or namely the AUM's, only work 100% with the re-circ type, because as has been previously said, the MAF throws a wobbler!

Reason being, its because the MAF cant re-calculate the correct air//fuel mixture values because the air needed to re-calculate has been dumped! Some people do say you can get away with a BOV, but i think thats personally down to the car itself whether it accepts or rejects the particular valve. So IMO, stick with a re-circ to be safe. The general consensus would be the Forge models. Never heard of a problem with one yet! And if you do still want a whooshing sound without any issues, then buy a Carbonio, they sound great! Just dont go in any deep water with one!

Hope that helps! [:)]
 

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Discussion Starter · #10 ·
I keep hearing stories that the Re-circ ones are better for VW engines? Can anyone confirm this?
Yes, that is correct!

Dump valves are meant for "dumping" excess pressure into the atmosphere, hence the term atmospheric. Thats where the whoosing sound comes from. VW's, or namely the AUM's, only work 100% with the re-circ type, because as has been previously said, the MAF throws a wobbler!

Reason being, its because the MAF cant re-calculate the correct air//fuel mixture values because the air needed to re-calculate has been dumped! Some people do say you can get away with a BOV, but i think thats personally down to the car itself whether it accepts or rejects the particular valve. So IMO, stick with a re-circ to be safe. The general consensus would be the Forge models. Never heard of a problem with one yet! And if you do still want a whooshing sound without any issues, then buy a Carbonio, they sound great! Just dont go in any deep water with one!

Hope that helps! [:)]
Thanks for the feedback folks!

Don't really want to get a Carbonio because I only just fitted a brand new Induction kit 2 days ago!

What about a twin pston valve?
 

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What about a twin pston valve?
I'm not entirely sure what the twin piston ones do...But it sounds to me like a double dump valve, if so that still wouldnt work.

P.S. No other induction kit will sound like a Carbonio on a MK4... Sell the one you've got and get one, it'll be worth it!
 

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What do you think is the best dump Valve for the 1.8 T? Diaphram? Piston? Twin Piston? Re-Circulating? what have you? ..........

What outways Performance, Looks or Price.......
I have a forge recirc on my 1.8T with a Pipercross VIS, no power gains that I can feel just a little smoother going through the gears when I am giving it a bit of stick.

Lasts longer than the stock valve (I believe) Looks good, and sounds bonkers when fitted with a CAI.........[:p][Y]
 

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Discussion Starter · #14 ·

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I have one of these ?40 DV's my car and it works great.Took it apart and its very well built., you also get the 3 different springs with it too.
At only ?45 delivered i you need to snap it up while its there.
Cool, I feel I may have to snap one of these up as I havn't got ?200 spare for a Carbonio at the moment.

What does your one sound like MO?
The valve alone will not make any sound as you may already know or not know, I had my Forge valve on with the stock air box and it was silent. It was only when I invested in a CAI I began to hear the "wush" of the valve dumping the air.

The Forge re-circ valve is ?100.00 ish direct from them. There has been some threads regarding the valve on ebay within the last month or so and as alot of people have said. The valves possibly have no warrenty. IMO I would save up that extra cash and play it safe and order from Forge
 

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I have standard airbox on mine and with the stereo off i can hear mine when i change gear.As said these valves appear to be very
well put together and with the benefit of the 3 differing springs.As pope said the standard D.V seems the best opperationally out of the bunch so i had been using the standard one till i saw one of these.
With regards to warranty im not fussed at all to be honest it works fine for me and is serviceable so im happy.So its not made by Forge, but it doesnt mean its not an equally as good product, so come on guys take of the Forge Motorsport blinkers for a few mins [:O][:p].
 

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Absolutely right Mo.  Dump valves are the most hyped things on our cars. They all do almost the same thing in almost the same way. If someone can prove that one is worth 3 times more than the other I'll be there (again) but having wasted my money on a relatively expensive one once for little or no gain I'm sticking with the cheaper items for now.
 
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