Jump to content

Forge blow-off valve (dump valve)


dimma02
 Share

Recommended Posts

I think Forge use OCT Tunings map who are an Austrian tuner. The Forge's dump valve makes a nice "TISHHHHHH" noise on changing gear. Not chavvy and over the top but noticeable... As standard the valve reciculates excess boost back into the system, their valve diverts this externally.

Link to comment
Share on other sites

[ QUOTE ]

I think Forge use OCT Tunings map who are an Austrian tuner. The Forge's dump valve makes a nice "TISHHHHHH" noise on changing gear. Not chavvy and over the top but noticeable... As standard the valve reciculates excess boost back into the system, their valve diverts this externally.

[/ QUOTE ]

There was me thinking that the recirculated charged air kept the turbo spinning between gear changes. Surely this would be a good thing. If you dump all that lovely charged air to atmosphere, then you have to recharge the turbine again and get it spinning. As we all know you only get maximum boost when the turbine is spinning, not when it's spooling up. Sure it makes an 'intresting sound' and all that but it is daft, if all it does is make your car slower. suicide.gif

Link to comment
Share on other sites

Hi Tian, (I keep wanting to hear some audio when I see your avatar! 169144-ok.gif)

This subject came up a while ago and the conclusion then IIRC was as you are saying....Nada/zilch/zero performance gain and probably loss! Plus I would have thought it much more likely to effect a VW warranty than re-mapping. I try to keep an open mind and that's why I asked the quezzie, to see what might be new or different.

Cheers 169144-ok.gif

Link to comment
Share on other sites

[ QUOTE ]

It doesn't dump it all, no power or driveability is lost. Tends to help if you find out what it does and fully understand it before commenting...

[/ QUOTE ]

Red, Silent Bob, don't ya just love him. 169144-ok.gif

As you wish, as you wish, but there's no need to be like that about it. We all have our own opinions and my advice is to hang on to it. Let's face it, nobody else wants it and this is just such a case. coffee.gif

Link to comment
Share on other sites

Ok, maybe this is a bit unfair as the title says "Forge blow-off valve (dump valve" and its not that kind of valve.

VAG cars use DV (Diverter Valves) of the recirculating type, so you don't get any dumping / blow-off, as Cupramax says.

But if you are inclined to replace such an item on your VAG car I'd say do it!

The VAG ones are known for their uncanny ability to split (internally) and although there is little or no loss in performance they do end up making a delightful flappy-fart sound when you lift off to change gear!

smile.gif169144-ok.gif

Link to comment
Share on other sites

[ QUOTE ]

Ok, maybe this is a bit unfair as the title says "Forge blow-off valve (dump valve" and its not that kind of valve.

VAG cars use DV (Diverter Valves) of the recirculating type, so you don't get any dumping / blow-off, as Cupramax says.

But if you are inclined to replace such an item on your VAG car I'd say do it!

The VAG ones are known for their uncanny ability to split (internally) and although there is little or no loss in performance they do end up making a delightful flappy-fart sound when you lift off to change gear!

smile.gif169144-ok.gif

[/ QUOTE ]

I replaced my valve on my Passat when I had it and it was a Forge unit I chose too. We have to be clear on the difference though as not all are aware. Blow off is blow off Recirc' is recirc'. Very different animals. Max Power boy racers fit the daft blow offs and they (in my humble opinion) are a chav addition to be avoided. bike.thumb.gif

Link to comment
Share on other sites

[ QUOTE ]

So, is Forge's valve for the GTI a "Recirculation" or "Blow-off" valve?

And does it enhance performance in any way at all?

And would it be likely to invalidate the VW warranty?

How would an insurance company view it?

[/ QUOTE ]

Forge is a Recirculation type - shouldn't fit Blow-offs to VAG cars, not good for them!

No performance increase.

Doubt it would invalidate warranty, as its a replacement part thats metal instead of plastic.

Doubt insurance company would care as its got Zero performance related increase.

I guess it kind of like chaging shi**y tyres for good ones!

169144-ok.gif

Link to comment
Share on other sites

I'm not sure you guys are talking about the new type. The old Forge 007P mentioned by Tian was a recirc type and directly replaced the factory part. The new one actually sits between the turbo and the existing DV so it still maintains stock operability but with better sound... The new valve is electronically operated by a solenoid.

Link to comment
Share on other sites

[ QUOTE ]

I'm not sure you guys are talking about the new type. The old Forge 007P mentioned by Tian was a recirc type and directly replaced the factory part. The new one actually sits between the turbo and the existing DV so it still maintains stock operability but with better sound... The new valve is electronically operated by a solenoid.

[/ QUOTE ]

Stick a linky up and let's all have a good squint at it. 169144-ok.gif

Link to comment
Share on other sites

Hmm....Thanks for posting the link but personally I'm not convinced it's worth spending £44+vat+carriage+installation for no performance gain and only the air sound. Agreed it's a fun sound but reading the Forge fitting instructions document I'm confused:

"Note, Due to the ECU controlled nature of the standard electronic diverter

valve you may experience longer than expected operations of the

atmospheric valve under certain operating conditions. This is not a fault in any way, the ECU controls the turbo pressure via the solenoid valve in order to improve driveability and soften the take up of power. In the same way you

may also experience non operation of the valve under enthusiastic gear

changes, this is also not a fault. It is determined by the ECU that the

recirculation is not required at this point due to the rapid re-appliance of the

throttle."

....Are they referring to their valve or the standard/stock valve?

Link to comment
Share on other sites

To answer my own quezzie!

Have just spoken to Forge and basically it's probably as everyone except me already knows! - There is no performance benefit whatsoever....It allows you to hear the 'blow-off' in the Mk5 FSITurbo - beautifully....It may effect your warranty according to individual dealer attitude....and some insurers may seize the opportunity to rack up your premium. It's very well engineered and it's up to you if you think it worthwhile.

Link to comment
Share on other sites

[ QUOTE ]

Hmm....Thanks for posting the link but personally I'm not convinced it's worth spending £44+vat+carriage+installation for no performance gain and only the air sound. Agreed it's a fun sound but reading the Forge fitting instructions document I'm confused:

"Note, Due to the ECU controlled nature of the standard electronic diverter

valve you may experience longer than expected operations of the

atmospheric valve under certain operating conditions. This is not a fault in any way, the ECU controls the turbo pressure via the solenoid valve in order to improve driveability and soften the take up of power. In the same way you

may also experience non operation of the valve under enthusiastic gear

changes, this is also not a fault. It is determined by the ECU that the

recirculation is not required at this point due to the rapid re-appliance of the

throttle."

....Are they referring to their valve or the standard/stock valve?

[/ QUOTE ]

No what they are saying is that the valve is ECU controlled and will not necesarily dump on every change as the ECU may not actuate it.

Also on the subject of power gain per pound you could say the same of exhausts. I wouldn't expect a gain on a performance exhaust unless you'd gone entirely turbo back with a sports Cat. Modern OEM systmes especially VAG ones tend to be well designed and the entire setup is only held back by the Cat and the ECU program.

Link to comment
Share on other sites

Well the sound of the Forge dump valve is quite annoying and I am regretting about it. Since the 2.0 TFSI engine's dump valve is ECU controlled and that makes it worse coz during partial throttle lift you will still hear the valve in action and the sound is surprisingly low pitch so at 1st I thought a double decker bus or truck is always around me. Unlike the vacuum ones for the 1.8T which would provide some performance gain, the new one for 2.0TFSI please try or listen before you buy.

Link to comment
Share on other sites

"double decker bus or truck always around you", very funny schemeloong, ha ha. i bet that had you looking at your rear and side mirrors all the time!! i think the gti is loud enough. my passenger tells me that people look when i take off from the lights in a hurry because of the sound/ or noise (depending whether you're enjoying coffee from a sidewalk cafe) from the motor/ exhaust of the gti. i don't want to start giving people the impression that this car is driven by jackasses.

Link to comment
Share on other sites

Please sign in to comment

You will be able to leave a comment after signing in



Sign In Now
 Share

×
×
  • Create New...