Hi there,
Canm you please let me know if I have a dump valve and what do they do?
I have a wrx 300 05 reg and met a security guard on a job the other night who said his mate has a dump valve and it makes it sound sweet?
Also any thoughts on an induction kit? I had one on my old car but will it knack up my warrenty etc?
Thanks.

 

sweet

 

You have a re-circulating valve ...

And a Dump Valve makes you sound like a ****!!

That Security Guard is earning £4 an hour because he's THICK!!

Induction kits KILL your MAF and engine and your warranty will be null and void.

Pete

 

Tell it like it is pete.

 

It's a shame, you see the security oficer spoke so highly of you! ( )

THanks for the info. I guess I will not be going down that route then.
All the best.
Martin

 

Don't listen to the scare people! If you want a car that makes a 'ptshhhh' sound when you lift off the throttle, then get a vta (vent to atmosphere).
I have to agree with the advice on the induction kit though, an uprated panel filter such as green or k&n would be fine.

 

Yeah, but who wants to look like a right *****????

Pete

 

Wise words from young Peter there!

 

I'm trying as best I can but I just can't disagree with Pete on this one.

cue the kevs/barry boys/etc. they'll be along soon.

 

If you want to know how ridiculous they are, then imagine one on an OAP's electric shopping scooter. They would be marginally less embarrassing on one of those.

 

I have to say, its only been Chavmobiles that I have heard them on ...... Subaru owners seem less afflicted by a desire to want to sound like a wet fart.

But, for how long?? The Chavs are taking over the Marque - and we will have to welcome these ***** with open arms even though their intelligence is just one step removed from a Chimp

Pete

 

.... Chimp Charriots

 

sooo, everyone recons dump valves are just for the fancy sound they make?? lol. i know they can dumps small quantities of fuel in to the cylinders on lift of, but is it not good to keep the turbo spinning between gear change?.

 

 

I wish we all had such an intellectual mind as yourself

 

Now that has a certain ring about it ......

Chav Chimp Chariots .....

BRILLIANT!!

Goes in my dictionary with CockLink

Pete

 

 

No, dump valves are not just for the fancy sound, all scooby's have them as standard from the factory.

They just come from the factory as 're-circulating' as opposed to VTA.
Just because it doesnt go 'Tsscch' like 5 GTT or Escort Turbo's etc doesnt mean it doesnt have one.

The only reason to fit a VTA IMO is exactly that 'vent to air' and give that 'Tsscch' sound.

Please somebody correct me if this next bit is wrong, its how I see it

A recirculating dump valve recirculates that excess air back into the intake after the MAF.
The Mass Airflow Sensor (MAF) will detect a volume of air entering the intake and the ECU will add the correct metered amount of fuel and were all

However, for a VTA BOV when it suddenly vents a volume of air out of the system, then your going to be missing a volume of air that MAF metered for, you've short changed it and the ECU doesnt question that its missing and is still going to add fuel for it.
so the amount of air that passed the MAF is no longer the same amount that will be entering the engine (you just vented some of it outside) but the extra fuel is still going to be offered, so you end up running too rich. This causing stalling and other running problems.

If it recirculates (using the Recirc' type BOV) back into the intake after the MAF, the air mass going into the engine will still be the same amount that was metered for as it passed the MAF.

Do the maths for this one

You could compensate for this to work with your VTA BOV with some engine management, I've heard mention of a MAP sensor system would help here

Am I right

p.s. a thought to take away, if VTA BOV's were so good would not Prodrive offer these as an upgrade part, would they not fit one as part of PPP if you needed one

 

What noise happens if you take the intake pipe out from the big box under the wing??

Pete

 

Vroom, Whoosh, ptishhht.

 

That's an extremely manly noise, Ali.