Looking at purchasing a new dump valve. Which make, model do you recommend?? The only ones ive heard & seen are Baileys & these coloured ones in Max Power. All help is much appreciated.

 

There was a post about dump-valves a while ago... There is a school of thought regarding vent-to-atmosphere (pssshshhh) dump valves being bad news, confusing the ECU and doing all sorts of stuff (higher fuel consumption, poor idling, damage etc etc).

On my MY94 WRX I had a bailey vent-to-atmosphere and just didn't get on with it, fuel consumption definately went up and it came off after a couple of weeks.

I was thinking about getting a recirculating type for my RB5, just to upgrade the stock model (plus they look nicer yadda yadda).

ta,
Matt.

 

Sorry to be thick, but how does a dump valve reduce fuel economy?? What does a dump valve actually do?? All i know is that it releases pressure making a piisssshhhhhhh noise.

 

My Forge DTA made no noticable change to fuel consumption, its always been terrible

 

meaga-stream

What is a Forge DTA?? I know Forge make dump valves but unsure what a DVA is. Is this loud & how much will i be looking at for one of these??

 

DTA is dump to atmosphere, the standard dump valve re-circulates back into the airbox... Which is part of the problem, when no air returns to the airbox with DTA, it screws up the fuelling. AFAIK.

I had one and it scared small children / passers by / old people etc. Also made the car cut at idle.

No performance gain... If you think your boost is high enough, that it would backpressure the tubo on let off, get a Forge Recirc, it probably has a bigger capacity and you will hear it more athough not to the same degree as an atmos. I found the K and N induction cone made a similar and more friendly noise, with a performance gain...

MB

 

HKS have an atmospheric BOV, however if you don't like the extra noise or it cause problems, for £12.00 you can buy an attachment which changes it to a recirculating kit.
Incidently for all the HKS BOV's we've sold, only one customer has wanted the attachment.
So maybe that means these don't cause many problems!!

David

 

Ive got a vent to atmosphere twin piston bailey dv, would this confuse the ecu and make it run like a bag of poo as i've not had it fitted yet ????????????

cheers RAZZ.

 

ive got a baileys installed and have not noticed any difference, but id like to see pics of people havin this installed just to make sure ive done it right!!

 

On my MY94 WRx it has had the pipe that goes back into the air box removed and just blocked off, now the recirculating dump-valve vents to air? and I don't have any problems. Should I change it for a HKS one or put the pipe back on.. I have had not problems and the owner before me has had no problems with it as well..

 

Maybe we need a new section to discuss these engine related matters.

Oh, hold on, we already have one

 

I've had a Baileys atmos dv on mine for a tank of petrol. Still managed to squeeze 280 miles out of my 60lt tank

I think the main reason people think the fuel consumption goes up is cause you're reving the engine more just so you can hear the sound

Matt

 

I have Forge motorsport DTA valve and no reported probs..
Using more petrol is a load of crap its only cos we are revving engines more to scare people!!!

 

So which DV would you say is the loudest on the market then?

 

So guys, do you reckon the DTA is better than the recirc then????

 

I don't think there's much in it preformance wise. If you want the noise get an atmos dv, if not, get a recirc.

Matt

 

Evo 5,

A dump valve releases pressure built up by the turbo when you let your foot off. The vlave opens allowing the trapped pressure to escape and lets the turbo keep spinning, so when you put your foot down there is no lag. Without it the turbo would stall and take a while to spin back up again. All turbo cars have them, nearly all recirculate for noise reasons.

Hope this helps.

MB