Dump Valves...

[paulus2112]

Inevitably, having owned my A4 1.8 Turbo for a few weeks, I am now wondering about dump valves...

Although I'm not sure if there is any point fitting one. The A4 has a mechanical recirculation valve, which (educated guess) sends the excess air back into the turbo rather than into the environment like a dump valve does.

Questions...

Would a dump valve upset the engine management system by reducing the air in the system?

Would a dump valve be a total nightmare to fit?

Is it in fact all lies about increased life of your turbo, better acceleration etc etc by fitting a dump valve when there is already a recirculation valve fitted as standard?

[macca]

A pet subject of mine..

Your recirv valve sends the airflow back pre-turbo (and after a MAF sensor if your car has one so that it is not confused). It's there for noise supression, to make the car as quiet to drive as possible with no compressor surge noise (commonly and misguidedly known as wastegate chatter).

If your car has a MAF then a dump-to-atmosphere valve will quite likely upset the EMS, though you can reduce the effects by having a twin piston design which is less likely to cause stalling.

It is in fact almost complete lies about the longevity of your turbo and better acceleration. Unless you're running seriously high boost pressures, and we're talking in the realms of 2bar+ of boost, you're not going to do any damage to the turbo without one. The difference between recirc and atmosphere and purely noise and whether you have a MAF fitted.

You're more likely to find slightly less smooth driveability and an increased fuel consumption in reality.

[paulus2112]

waste of time and money then?

[macca]

Personal choice, but I'd say yes. My girlfriend would heavily argue the point though as she likes the 'woooosh' noise of a dump valve :rolleyes: lol

[nunchukhamster]

I'm with Macca on this, waste of time (in fact, on the ME7 engine management my Volvo runs you can't run a DV as it massively upsets the ECU as it's a closed system and the car just thinks it has a boost leak and throws a load of fault codes).

IIRC, Forge do make one for the VAG 1.8T engine.

[macca]

The Volvo runs a MAF as I was talking about, which is why it upsets the EMS. It meters the air going in to the engine, which then disappears and it can't work out where the air has gone. Older systems fuel for the air resulting in a big rich condition and usually stalling, newer ones realise and throw a wobbler!

[paulus2112]

The wooshing noise is a neat thing, I am harbouring delusions of WRC grandure however I hold a massive distaste for cars pretending to be something they're not - Vauxhall Novas making dump valve noises for example!

My question is answered, no dump valve required... Superchip on the other hand........ :innocent:

[nunchukhamster]

Superchip on the other hand........ :innocent:

NO!!!!!!

If you want it mapped, get it done by a REVO dealer, there is a very good one in Portsmouth, http://www.jkm.org.uk/performance/ecutuning.htm

[Ang]

Personal choice, but I'd say yes. My girlfriend would heavily argue the point though as she likes the 'woooosh' noise of a dump valve :rolleyes: lol


The sound of dump valves :inlove:, must be a female thing.

[macca]

NO!!!!!!

If you want it mapped, get it done by a REVO dealer, there is a very good one in Portsmouth, http://www.jkm.org.uk/performance/ecutuning.htm

Haha, beat me to it. Superchips aren't the best by a long way, just the one everybody has heard of.

They don't have the best reputation though I think some of their more recent stuff is a bit better. I remember the GT4 'chips' were just a resistor that removed fuel cut, but for a lot of money!

You can't beat a remap by a reputable dealer, and you'll be glad you did it that way :)

[paulus2112]

NO!!!!!!


I had a feeling 'superchip' may have generated this response! I'll look into the options when I know if I'm def keeping the car!

[lambo-lude]

everytime i hear a dump or chatter valve i think of rst lol

[paulus2112]

As in RS Turbo? I get that, or Renault 5 GT Turbos...

Not appropriate company for Audi A4!