danwrx4

Happy new year all, i have a baileys dump valve fitted on my 97 wrx, its the one when you let off the pedal it makes a sound... is this really worth it performance wise because it never really shows off the car as it only makes a noise on the motorway or if you give her some beans and then let off??

Multijfj

Well ask yourself, why do you want a dumpvalve? If you want with sound, go and get one with sound! If you dont, then get a recirculating one which does improve performance a little, but nothing noticeable id say

andy_s37

Dan the chances are that if you strip it down, clean it out and regrease it you will get the noise back. Baileys i've had in the past usually make noise at low pressures.

Andy.

danwrx4

when it does actually make a noise it is quite load, the ones i heard before usually go of as you accelerate rather than decelerate though

JohnD

iTrader: (5)

With due respect, Dan, I think you need to swot up on what a dump valve actually does? Your engine was fitted with a perfectly good dump valve as standard. Fitting an aftermarket version which vents to the atmosphere as opposed to back into the induction system, as the original does, is for the noise it makes (unless the original has failed in some way)
If the ones you've heard have made noises on acceleration as opposed to lift off, then there is something strangely wrong with them?
JohnD

martx

I love a bit of 'WHOOOOOOOSH!', always have always will.

I've just ordered a forge atmospheric (can't spell it!)

mart

Elmer Fudpucker

Blow-off Valves

Dark Blue Mark

LOL John

MB

BedHog

That is just his opinion. One has to doubt that anyone could actually feel a difference between a recirculating and blow-off valve in everyday driving.

Elmer Fudpucker

BedHog

It's true.

I've never seen anyone quote figures. If they did I would assume it would be in the order of 0.01 seconds slower for a quarter mile...

The only real consideration for a blow-off dump valve is whether you want noise or not.

Please feel free to contradict this with REAL facts, not myths.

Dark Blue Mark

Or if you want it to screw up your fuelling....

MB

BedHog

The amount of time that this condition actually exists, compared to when you are in gear and driving is miniscule. Do you really believe it's important?

How does the ECU know how much air actually gets re-used and how much escapes from the pressurised manifold back through the air filter? The amount will surely depend on how long the gear change takes.

Plus if people want an audible blow off noise, they probably wont be too upset about a few pops and bangs which might result from running rich momentarily (better than running lean, no?)

Damocell

iTrader: (1)

I could feel the difference, not in acceleration but in driveability of the car, recirc wins everytime for me....but I really do miss the noise!

Damo

Damocell

iTrader: (1)

the over fuelling comes from MAF revertion and if the dump valve is constantly venting at part throttle on the motorway

Post number 19 on this thread explains it brilliantly

https://www.scoobynet.com/drivetrain...highlight=jolt

Damo

andythejock01wrx

Can you explain in detail what difference you felt on removing the BOV ?

Damocell

iTrader: (1)

https://www.scoobynet.com/general-te...valve-wow.html

Damo

andythejock01wrx

Cheers Damo. Interesting read.

My 01 WRX had a Baileys dump valve on it when I bought it 6 months ago.

Thinking about swapping it for OE, but was concerned that the car might be less responsive (it's good at the mo).

BedHog

My car feels better with the HKS SSQV.

Before, the car seemed to keep going for a couple of seconds after releasing the accelerator, with the HKS the revs die instantly. Plus I do like the sound...

Dark Blue Mark

Bed Hog,

I know the issues around VTA's extremely intimately, which allows me to post about it with some knowledge.

Do you knw any "good" mappers that will tell you its a good idea?

Think its all a bit gay just to get a hissing noise

MB