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Scanny
22-11-2012, 08:07 AM
having read the links that show up i still have no idea what i want. i just know i dont want the one i have and i dont want it where it is located (bottom of the car behind the bumper) so what should i get for a manual legnum that does what it is meant to do and makes a nice sharp sound as opposed to the phssssst that i currently have

with links if possible so i can see what is suitable

BillHardy
22-11-2012, 09:43 PM
Richie,i have an R2D2 not yet fitted to the car if you want to give it a try for sound effects

Scanny
29-11-2012, 07:34 AM
i have no idea what that is or if it is of any use to me Bill. there are so many different variants that i was hoping for some guidance but it looks like i will have to ask the experts rather than experienced. there is a place near me with a good reputation with performance cars so i will try them

elnevio
29-11-2012, 10:47 AM
It's a very subjective area, to be honest. :sigh:

Humpty's Revenge
29-11-2012, 10:49 AM
58971

Am I thinking the wrong type of dump valve?? /haz

elnevio
29-11-2012, 10:57 AM
/lol

Gingerfish
29-11-2012, 11:29 AM
I have an HKS SSQV II if that helps. I could try to do a little vid later on and post it up so you get some idea of effect if you like Richie.
It can be loud but only if you're gunning it.

Pugme
29-11-2012, 11:48 AM
I have an r2d2 and they make a very loud ptshhhh noise.

Scanny
29-11-2012, 03:09 PM
i did some reading on the forum and i am totally lost. i have no idea what a recirculating valve means and there was mention of blocking something off. Steve had one for sale that had a hard pipe i think? there seems to be a possibility of different valves for auto and manuals. a loud noise would be nice but at the same time, it does serve a purpose and i dont want one that makes a noise without doing what it is actually meant to do.
thats twice a R2D2 valve has been mentioned so that may be a safe bet but is there any modification required or is that a straight fit and where does it fit?

i assume i will need to replace the pipe that the current dump valve is fitted to when i have it removed. apparently it is fitted in a strange place but as its right at the bottom behind the bumper, its positioning was more to do with being heard rather than doing its job. i would prefer to have a dump valve where it should be from a performance point of view but i have no idea where that is

The Vee
29-11-2012, 05:38 PM
If you're not bothered about the noise, and performance is foremost you maybe better off getting a metal one off an evo. While dump valves do not improve performance on their own they can restore what you've lost if your old one is faulty. These cars are designed for the recirculating type. Open ones make the noise and some combine both. They can be a constant source of (minor) problems with driveability etc if not setup correctly and can indeed affect fuel consumption in an adverse manner. I forget which Evo you need but I'm sure someone on here can help. I run a combination one myself and after a lot of fiddling it's not too bad.

horndog
29-11-2012, 06:10 PM
Evo 8MR is the metal Recirc BOV. EvoX also fits

Colin Wiltshire
29-11-2012, 06:27 PM
I have a Blitz 1 that sits on top, replaced 1 of the flexi pipes. Looks good, I like it there, but doesn't seem loud enough for what I like

John TheAntique
29-11-2012, 07:10 PM
I've had four in my time, the recirc, an evo one, a Forge combination adjustable very expensive one, one with several diferent strength springs but for the last two years I've used the cheapest, Amber Performance "Nomad" (I don't think they market it under that name any more but still the cheap one). It makes a lovely loud noise when pushed and I've had no problems with stalling or anything else.
Eurospec supplied and fitted it, Gowf had one on his manic VR4 say no more.

zanzibar
29-11-2012, 11:00 PM
i also had a nomad dv on my car for 7 months and it sounded awesome but i started getting the dreaded stalling issues so removed it. i would personally recommend a recirc valve.

Jesus-Ninja
30-11-2012, 02:08 AM
I'd also recommend a recirc. It all depends on what you want one for of course, but if you want to keep stop turbos stalling and keep correct air metering and fuelling, then a recirc is the fella to get :)

Scanny - the dump valve vents excess boost from the system when the throttle closes. The stock setup uses a recirc, which means the vented air is red back into the system, between the MAF and the turbos. This means the turbos can vent, but the MAF readings are still correct, as nothing is leaving or entering the system except via the MAF (the dump valve is moving it around, but within the system, behind the MAF)

A non-recirculating one is one which makes the Tsshh noise. Rather than recirculating the air back into the system, it vents to the atmosphere. The downside is that the MAF is reading air coming in, but a lot of it never makes it to the cyclinders, because it's venting via the dump valve. As a result, things go rich, which can be nice if you like popping and flames :D It can be a bit of a pain on partial throttle though.

Scanny
30-11-2012, 06:51 AM
I'd also recommend a recirc. It all depends on what you want one for of course, but if you want to keep stop turbos stalling and keep correct air metering and fuelling, then a recirc is the fella to get :)

Scanny - the dump valve vents excess boost from the system when the throttle closes. The stock setup uses a recirc, which means the vented air is red back into the system, between the MAF and the turbos. This means the turbos can vent, but the MAF readings are still correct, as nothing is leaving or entering the system except via the MAF (the dump valve is moving it around, but within the system, behind the MAF)

A non-recirculating one is one which makes the Tsshh noise. Rather than recirculating the air back into the system, it vents to the atmosphere. The downside is that the MAF is reading air coming in, but a lot of it never makes it to the cyclinders, because it's venting via the dump valve. As a result, things go rich, which can be nice if you like popping and flames :D It can be a bit of a pain on partial throttle though.

does the EVO 8 and X meet the requirements that you would recommend? i seem to be leaning towards an EVO trend with the brembos and bonnet etc so i may as well go with the EVO one if it is a good one for our cars. it is a little annoying to upgrade with EVO parts when the EVO was born from a VR4 in the first place. our cars seem to have got a bit of a bum deal there

CANDEE
30-11-2012, 09:27 AM
Richie, the evo X one seems to be the current ozvr4 one of choice as you can use the factory vacuum hose. You can also use the evo 8 MR one too, but you will need to replace the vacuum hose to the bov as the connection is on the other side.

Scanny
30-11-2012, 09:33 AM
1st choice is EVO X then, failing that, EVO 8. thanks. cant find anything on ebay yet but there is no rush. i need to slow down anyway and clear some jobs that are already outstanding. buying some alloys might be a good start since i dont actually own any that i can use

Gingerfish
30-11-2012, 02:13 PM
I don't know how to insert the vid directly.
Hope this helps...

http://m.youtube.com/index?desktop_uri=%2F&gl=GB#/watch?v=tgQ8dAKi12I

Scanny
02-12-2012, 01:16 AM
where SHOULD the dump valve be? there is no point in giving me the technical details so lets say i am at the front of the car looking at the engine. where abouts would i see the dump valve when it is correctly positioned?

Subaru ETA
02-12-2012, 01:28 AM
Eerrr it is behind the bumper under the car like you said. It sits in front of the gearbox and you can only see it from under the car. That is where is is supposed to be....

Scanny
02-12-2012, 02:43 AM
Gowfs engineer mate said it was in a strange place and i thought it would be somewhere near the turbos. still not keen on it being there. its the lowest part of the front of the car and im not sure how much damage could be done if it did get ripped off. that would obviously leave 2 pipes with open ends. cheers for letting me know though

Subaru ETA
02-12-2012, 04:14 AM
If you managed to rip it off you would have ALOT bigger issues then just that. It sits higher then the sump so you would have to rip the sump off first!

SEAN-NZ
02-12-2012, 05:51 AM
you can get fairly loud recirc valves, mines recirc and i get looks coming off boost, even scared a few people i think :/, couple mates have also commented on how loud it is

Jesus-Ninja
02-12-2012, 09:26 AM
The trouble with where the stock one is located is not where it's plumbed into the system, but rather where it physically sits. It's low down and as a result gets covered in crap. Not such an issue for a recirc, but a vent to atmosphere can get that crud inside it which stops it working. I had this and it kept sticking open.

Ideally it should vent from as close to the butterfly as possible (which the stock one doesn't) and then just needs to feed back in anywhere between the MAF and turbo. The stock set up does this just after the inlet splits. A better design might be to do it before the spilt, but I'm not sure it's much of an issue.

If you ran MAP or a blow through MAF, the fuelling issues associated with vent to atmosphere would go away.

Sent from my GT-I9100 using Tapatalk 2

elnevio
03-12-2012, 04:54 AM
Oddly enough, I never experienced fuelling issues while I ran a VTA dump valve on the VR-4. Mine was positioned in the big hose that's next to the inlet trumpet, above the gearbox.

Evolved
12-12-2012, 08:39 AM
http://www.forgemotorsport.com/

for a sharp tish instead of peow (hope that make sense)

but dump valves are annoying for high speed driving.

andyleaves
12-12-2012, 10:13 AM
I have this one from Forge... (http://www.forgemotorsport.co.uk/content.asp?inc=product&cat=&product=FMBSPLTR) Fits a treat, no worries about ripping it off, you'd shag everything else first!

Make sure you get this one the FMB version and not the other, this is marketed for the Colt ctz thing but work well with our cars.
The major benefit, is that you can swap it from re-circ to hybrid. You can also run it as full VTA, but not IMHO a worthwhile venture...
In hybrid mode you get the psstttt, but not the fueling issues.

I have mine in hybrid mode, and the psst is not too loud, but def clear an audiable.