These " Splitter" Dump Valves

[Frazzly]

Hey guys,

Just wandering if anyone is or has used these splitter dump valves. You know, the ones which you can adjust how much is recirculated and how much dumps.

Just wandering what folks experiences of them are? Ive got to admit. every turbo car Ive had has had a dump valve and I miss it from the a4 so Im tempted. Just wandering if there worth it or if the sound is rubbish.

Im planning a remap in a few weeks along with a possible air filter too.

Noticed theres a forge splitter and some other cheaper one out there available.

Cheer
Fraz

 

[g60leigh]

I tried an atmospheric DV and it makes the car run like a bag of spanners so went to a re-circ which is very quiet, recently changed to cone filter and can here it as well as any atmospheric now and no running problems.
I would suggest a forge re-circ and cone filter if you want troble free running with the ptshhh

 

[DPM]

I'd say go for the Forge 007P. Best selling replacement valve available.

Damian @ DPM

 

[g60leigh]

I'd say go for the Forge 007P. Best selling replacement valve available.

Damian @ DPM

I got my from Damo, top guy, full of excellent advice

any chance of some discount LOL

 

[DPM]

Maybe a slight chance Leigh!

 

[brendan]

i don't have a turbo car, but out of interest which part is it you replace that gives wastegate chatter rather than a "psssshhhhtt" from a normal dv?

 

[aragorn]

"wastegate chatter" doesnt exist

The chatter noise you hear is called Compressor Stall and its exactly this the dump valve is fitted to prevent. When you close the throttle without a dump valve fitted the turbo is still spinning at high rpm trying to force air into the inlet, the pressure builds up and the air starts to flow backwards thru the turbo compressor, which causes that noise and quickly stalls out the compressor.

Its bad because the rapid stall can cause the shaft to snap, plus the stalled shaft now takes longer to spool back up once your back on the power

A dump valve opens and releases or recirculates the pressure in the inlet which stops the compressor from stalling.

On something like a cossie with a dirty brute of a T3 turbo you can get away without running a dump valve and get the stalling noise all the time because the turbo shafts are pretty sturdy. I wouldnt vouch for the shaft in the diddy turbo fitted to the 1.8T holding up to it for any length of time though.

Some dump valves can be configured to only open under a certain pressure, this causes compressor stall at low boost levels where there is less risk of damage to the turbo shaft yet still dumping normally at higher boost levels, seems to me thats only useful for folk wanting to drive around their asda car park annoying everyone as it serves no purpose.

IMO i see no benefit fitting an aftermarket dump valve when the bosch 710N valve is so cheap new from audi

 

[Dans-first-Audi]

Basically - block the DV hole off with the end of a broom stick

 

[brendan]

awww... i'd be looking forward to "wrc-style" sfx if i ever got round to buying a tq/s4/tt - ah well :'(

 

[ALPINE]

thing i dont understand is.... i have a re-circ system on mine that is set up no different to a factory fitting. ok i have an aftermarket cone filter and a forge Re-circ. just because its not a "Audi Re-circ" it still works in the exact same way. my car chatters like an old woman on the 99 bus. how is this hurting my turbo when its doing as audi intended. i have just fitted a Large cone filter which has no difference to how my DV re-circs. ??

 

[aragorn]

if it chatters in your setup then i presume the forge dump valve simply doesnt open at low boost levels as i mentioned above.

The stock setup might even do it but you cant hear it with the normal airbox etc fitted.

 

[Phantom_A4]

Forge split r's seem to work ok on my friends 1.8t and s4. Comes with 50+ different settings to stiffen the valve so it only dumps on real high pressure, or dumps if you have a slight twitch on the throttle. They seem to run fine IMO, you just need to adjust the settings to your particular car taking bhp/turbo etc in to consideration and it should be fine. A poorly adjusted one will definetely ruin the performance and could damage your engine. So if you know what your doing fit one, if not and you still want one get it pro fitted and tested.