Dump Valve Noises... + SSQV's?

[pietch]

Hi.

My Octy VRS is Jabba'd and the aftermarket forge valve makes a 'woosh' when I lift off the throttle above 1500rpm, is there anyway I can make it run quiet?

Also has anyone tried these two stage dump valves in there VRS:

http://935motorsports.com/catalog/im...KSSSQV_big.jpg

"HKS Super Sequential Blow Off Valve - The Super Sequential Blow-Off Valve (SSQV) is a pull type relief valve. This means that pressure forces the valve shut unlike most valves which are pushed open slightly under boost. The SSQV is actuated by pressure alterations only, ensuring quick valve response and complete closure during idle. Typical blow-off valves utilize large valves in order to accommodate high boost/high hp applications. However, these large valves react slowly and require high activation pressure to open. Smaller, fast reacting valves, do not permit the air flow required for high horsepower. The SSQV incorporates both for maximum performance. It is engineered utiliizing a small primary valve and a secondary valve for additional relief capacity. The SSQV is made of billet aluminum and emits a unique aggressive sound."

[Goochie]

You can use a standard OEM DV - The part number for the VRS item is the same as for the higher powered TT's.

I tried a standard one and it was muc quieter than the Bailey I normally use - no differencein reaction speed either.

If anyone has an OEM DV they dont want anymore please let me know

[pietch]

Why do Jabba sell and recommend the Bailey obes then I wonder? Might put my standerd one back I think?

[Goochie]

Jabba sold me a Bailey too - and threw my old one in the bin because I said I diddnt want it

The "Viper" DV is much quieter than the bailey though.

[pietch]

What is a Viper DV?

[Goochie]

Does the same job as the Bailey/Forge item, but made by a different company.

[DaveU]

Apparently the HKS Super Sequential ones work with remapped 1.8T - alot of the guys on www.vwvortex.com use them - do a search. I dont know of anyone using one over here. I was going to get one but they are a lot of money and you get exactly the same result from fitting an induction kit such as the one from ABD that i have and can thoroughly recommend

[SkodiRS]

Originally Posted by pietch

Why do Jabba sell and recommend the Bailey obes then I wonder? Might put my standerd one back I think?

Previously the OEM DV weren't very relaible...the diaphragms kept on splitting. Forge/Baily are piston types and are more relaible. Jabba recommend the Bailey as you don't generally have to touch them.....they can be serviced by Bailey.

Get a new DV from your Skoda dealer...not expensive and the new ones are more reliable.

[pietch]

Jabba told me that the TIP was perfect on the RS, any bigger and it would stall the turbo.

I already have a green cotton filter, just wondered that if the SSQV valves are two stage they will not dump unwanted boos pressure, just what is required not to stall the turbo, so in theory if you had a part throttle lift at 3000rpm for 1/4 sec you could then re-apply the accelarator and boost would come back on faster and less boost was wasted during part throttle lift off.

This sort of makes sense to me. Just wonder how it works in practice?

[pietch]

Found this on vwvortex forums : http://forums.vwvortex.com/zerothread?id=2407740

[150HP&counting]

Originally Posted by DaveU

I was going to get one but they are a lot of money and you get exactly the same result from fitting an induction kit such as the one from ABD that i have and can thoroughly recommend

Yeah nice bit of sound the abd CAI makes aint it

[johnjohnhealy]

I had the HKS one on my MR2 Turbo's, It does respond quicker than any standard dump valve but you'd never be able to tell just by listening, we're talking milliseconds, the sound is quite different to most valves as it's 2 stage so you get the initial higher pitched 'pitish' noise from the quick response bit followed by the 'whoosh' from the main bit.

The main point that everyone seems to be missing here however is that the Standard DV is re-circulating, in that the air it vents is vented back into the intake system after the MAF so there is no loss of measured air. the HKS etc are vent to atmosphere so you hear the noise louder but also lose some measured air from the intake system, some people dont like this as it's possible that the car could run too rich as the air the ECU thinks is in the intake/engine actually isn't any more.

[pietch]

This SSQV is 100% recirculating:

http://935motorsports.com/catalog/im...KSSSQV_big.jpg

Just like OEM.

[doEboY]

whenever i've stood by and watched a scooby go past "blowing off" as it changes up the gears i've stood in awe! i love that sound! I'd count it as part of the driving experience that came with the car. I'd give my left, right and centre testicle for that!

[MC Bodge]

Originally Posted by doEboY

i love that sound! I'd count it as part of the driving experience that came with the car. I'd give my left, right and centre testicle for that!

I tell you what, I'll rig up a system with a big compressor driven off the crank that charges a pressure vessel and gives a massive whoosh when you press a button. I don't want any of your testes though, just £10K

[pietch]

Does anyone have an original HKS for sale?

[DaveU]

You probably wont find one on here - to my knowledge ive never read about anyone trying one - that's not to say it hasnt been tried of course! Best place to look would be ebay (.com), vortex or failing that a jap car site (nissan 200, skyline or pulsar - although bear in mind you might need an adaptor or something).
Be interested to know how it goes - purely for research purposes you understand