Sorry if this is a repeat thread – I realise there are a million on dump valves.

My deal is that I have acquired a 2005 Blob STI Type UK. It came with a Turbosmart Supersonic dump valve and the original air intake and air filter have been removed / replaced. The result is that it does not make the usual WOOOSH sound during gear changes, but a sound I can’t really describe – perhaps a squirrel going through a mincer, or perhaps a high pitched fart?????

Two questions, 1) is this usual/OK or should I investigate?

2) What parts do I need to buy from Subaru UK to get the car back to standard – I phoned their parts department and they couldn’t help.

Thanks all.

 

I reckon ul need air box an the standard recirc valve check eBay or breakers yard will be cheaper than main dealer, sell the dump valve and treat urself to a k&n panel filter.

 

As for the squirrel farting I don't know much about dump valves. But someone will.

 

Yep, get back to standard, the car will feel much better. Do you know, however whether the car was mapped for the chav horn and breathing mods? It may ned a tweak if it was or checking by a mapper to air on the side of caution.

It makes a nice change to see people taing these bloody useless contraptions off as opposed to putting them on and requesting how many bhp increase they'll get LOL

 

It's good that the OP has realised at an early stage of his scoobynet career that dump valves are no good and he wants to go back to the original specification

He realises that they sound stupid and people just laugh as you drive past going

Wwwhhhhooooosssshhhhh and ppppssssttttt

Infact dump valves and subarus are like chavs and Burberry

Not an ideal match at all

 

Also avoid K&N, if you leave it oiled it may contaminate your MAF. Either use OEM and change it regularly or get a Subaru approved Pro-R which is foam.

 

K&N panel filter must be better than oem surely?

 

These dump valve threads always make me laugh when the same people come out the woodwork and start throwing around the chav, Burberry and mcdonalds references

 

K&N filters covering the maf with oil is rubbish. It's only a thin layer of oil on the filter and it doesn't move. It only becomes a problem if some Muppet re-oils it and drenches it.

 

Why? Truth hurts?

 

I was mortified to discover a Bailey air bypass valve on my 944 Turbo - set to recirc, at least!

 

It don't hurt me mate, my car is standard, apart from PPP.

 

I'm not convinced... a new OEM flows as much air as a K&N, the only thing is they get clogged quicker. If you replace them frequently they are just as good.

 

I disagree, I have had a factory fresh K&N contaminate my MAF on my Beemer and has also happened to friends. My mechanic has seen it countless times.

Subaru give a warranty on the Pro-R filters and one of their selling points are it is dry foam that doesn't contaminate MAF's.

You CAN wash and dry a K&N to rid it of the oil, but why bother?

 

I've got a complete airbox with STi filter, inner wing resonator etc. sitting here if you want to go back to standard intake.
As I'm also in Romford it might be worth popping round for a chat if you need a bit of advice?

JohnD

 

Another romford lad. Welcome and well done for having common sense. Get the standard air intake back on and a cosworth filter from lateral Ł25 ish. As a rhle of thumb any scoobies i hear that have chav valves dont get a wave from me lol

 

Unfortunatley, if you run some form of induction kit with an open filter even a re-circulating dump valve can be clearly heard, although nowhere nearly as loud.
The OP has a Turbosmart Supersonic which I assume is vent-to-atmosphere?

JohnD

 

Yep, one of the noisiest chav trumpets on the market

 

400 bhp + on a K&N filter in some of the Subaru's by Litchfields?

 

So? Just because it suits one application doesn't mean it suits another. Over the years I've seen competition cars that never bothered about filtration. That's fine, as they do regular engine rebuilds. What they want is air flow above all else. A road car, well, a road car that you want to last needs filtration as well as air flow and it's a balancing act.

Most engines around 400bhp won't be using the MAF and a standard air box. In this case a K&N may well be fine, however on a standard car with a standard air box and a MAF then IMHO you're asking for trouble with a K&N. It "can" contaminate a MAF. Of course a washed K&N does give more airflow, but then it gives less filtration and that's bad for your engine.

Ask the mechanics/engineers who've been around them and they'll tell you on a standard car anything other than a "clean" OEM filter is a con. Save your money for V-Power, it'll do you more good.

Or for me, running about 340bhp, a Power-R dry foam filter, gives a bit better air flow and reasonable filtration. It costs more than an OEM but can be cleaned every year. It also doesn't affect the warranty from Subaru, not that I have any left...

 

Funny that the CS400 and the Litchfield cars use the standard air box and MAF.

 

You need one of these bad boys

 

I was meaning modified 400bhp cars, and surely the Cossie uses a Cosworth filter? And you mean Litchfields imported JDM cars?

Anyway, it's not a point scoring competition, use a K&N with a MAF if it makes you feel better. All I'm saying is, I have had a MAF contaminated by a K&N and so have others.

Why did Subaru get Pipercross to design them a dry foam filter that specifically "avoids damage to MAFs" ????

It's your money, do what you want.

 

I will get a photo up this evening of my engine bay and show you all exactly the situation and then work out what filter to go for.

 

Here you go, pictures regarding the dump valve and the air box:

The car:



The valve - it was set to it's softest setting, I have now set it harder:



The air intake - or lack of. Is it ok to leave it like this or shall I take make sure the intake goes back on asap:



Any comments on the engine bay in general?



Thanks all.

 

dump valves are not chavvy,lexus lights are chavvy,stick on L.E.D light up washer jets are chavvy,my dump valve makes a high pitch sound at high revs,im not that keen on it to be honest i keep thinking an eagle is gonna swoop down and stuff a beak full of worms down my bonnet scoop

 

update - adjusting the dv made zero difference, lots of what sounds like turbo chatter. time to go to recirculation!

 

If there is a facility for increasing the spring rate then it could be that it is now dumping just a small amount of the pressure, causing the chatter you describe.

Removing the air intake is a very strange mod. Completely pointless!
It takes cold air from the front of the car. The air entering the airbox is now drawn from the engine bay (and warm) through the hole left by the removal of the intake! Weird! Is the resonator still bolted in the inner wing? I would assume it is, as I couldn't see the previous owner having the savvy to remove it! If it is and you have the intake, put it back on.

JohnD

 

To be honest I think the spring might be broken as it is not dumping at all.

I agree, was wondering if the air intake had been removed during a service and had forgotten to be replaced.

I didn't see the resonator, pretty sure that has been removed. The first thing you have is the standard, large black air box. Either way I need to get the original parts back on!

Sadly the previous owner had no spare parts, having sold them all on ebay!

 

I think the only reason for the intake to be removed would be to give better access when doing a cambelt change. I don't think there's any way it could be forgotten!
Removing the resonator was a mod some people did some while ago but leaving the intake in place to feed cool air to the inner wing.
Unfortunately, although I have the resonator here, I have re-used the intake (in much modified form) to feed air to the cone filter. You could however, rig up an air duct tube from behind the fog lamp cover to the entry to the air box, in the inner wing. Having said that, I would imagine there's someone on here with the intake going spare and maybe an OEM or aftermarket re-circ. dump valve.

JohnD