Subiehatch

Hi guys i have been debating whether to put dumpvalve on my 2.5 2008 STI hatchback or not.
Will it do any damage ?
Will i have to remap it after being installed ?
Anyone done this on theirs and recomend ?

**jay**

iTrader: (1)

Its already got a very good dumpvalve on it, if you want to put a chav one on that vents to air and causes running issues ?

Sarg400

iTrader: (1)

2008 2.5 you need too wrap it up in cotton wool, let alone put a dump valve on it lol...

**jay**

iTrader: (1)

Even putting the incorrect air freshener in it can cause it to have a tantrum and crack a ringland lol

Subiehatch

Haha lads very funny.
No really for real ??
I appreciate the banter but would i be able to put one on or not ???
I heard it could cause running issues.

Anyone that has a hatch comment below if they have put one on ????

Subiehatch

Youll be surprised mate.
My hatch runs like a dream !!!
😂😂😆😆

alcazar

iTrader: (2)

It's your car. You seem to have made your mind up, so go ahead.

But I re-iterate what has already been said: be VERY careful with that engine. I would NOT do it.

Subiehatch

Thats why im here mate asking for advice.
Thats what i been hearing.
Its a very weak engine and could go wrong at any stage.

Ive had many subarus 2.0s and 2.5 but never seen a 2.5 with a bov.

alcazar

iTrader: (2)

Ask yourself why you want one?

The car HAS one, it runs well with it.

Why change something that's working for a daft noise? The VTA dump valves can cause over-fuelling which CAN lead to borewash, oil contamination, exhaust valve overheating, damage to exhaust manifold and damage to CAT's.

There will be those who tell you theirs runs fine with one.

But as I said, your car......

Always bear in mind that those giving advice will NOT have to bear the cost of any repairs. That's why I err on the side of caution...I have experience of Subaru repairs and they ain't cheap

Subiehatch

I always liked the oooooshh
But after reading your comment i think i will stay away from it.

If its really that bad then no i wont touch it.

So the 2.5 are not meant for bovs,what about recirculating valve ?

Thanks Alcazar

scotty boy 80

iTrader: (5)

Mate if you want to put a dump valve on it go for it, alot of people on here like to go on their high horse about a dump valve being a chav horn and it will damage your engine and it's the same idiots that comment every time, it won't damage your engine or anything like that you might find gear changes were smoother with the standard one on but then your getting no sound, stick to the like of HKS or forge motorsport stay away from baileys there cheap and poorly made

Subiehatch

Thanks Scotty Boy

**jay**

iTrader: (1)

If you want a woosh noise and reliability buy a lorry

Subiehatch

Jay 😂😂😂 i am a lorry driver actually haha i dnt do it for living though !!

**jay**

iTrader: (1)

Lol me too thats why i could not live with my car making the same noise as my truck

Joking aside its your car to do as you please but think you will find the downsides of possible running issues just for a noise will end up reverting back.

alcazar

iTrader: (2)

So we are idiots for putting our point, and saying what MIGHT happen?

And you don't think that the smoother gearchanges WITH a recirc valve are anything to worry about?

Will YOU fund his repairs if it DOES go **** up?

You couldn't make it up.

alcazar

iTrader: (2)

You already have a recirculating dump-valve. The one you have is fine. It is good for up to 1.5bar.

CharlySkunkWeed

iTrader: (7)

I ran a DV on my 2.0 with no issues , didn't notice any changes in driving the car other than the noise. It ran with it for years before i owned it then i got car mapped , ran with it for a while then bought a standard on in fear of it doing damage. Never noticed any issues either fitted or not , actually missed the noise.
BUT , I'm picking up a 2.5 hatch this week and i wont be modifying it in any way if there's even a hint of doubt of causing issues as its not worth the risk.

Subiehatch

Hi mate you will want to modify it believe me.
Ive had mine for 4 months standard.
Im on the process of getting all my mods together than bolt it on for a remap.
You cannot have a subaru without an exhaust.

I dnt see what the issue is with a bov.
All its doing is letting the pressure off from the turbo out when not accelerating.

I have been hearing good and a few bad opinions on it but the majority have been good no issues whatsoever with them fitted !!

🙄🙄🙄

BrownPantsRacing

iTrader: (6)

I've ran with standard DVs and aftermarket VTA DVs of different types at different times with absolutely no adverse effects on the cars running. As mentioned already, there are chances it could increase fueling and lead to bore was etc etc etc, but it makes such a marginal difference it's not worth worrying about (as confirmed by various mappers). There has been no documented evidence that an engine failure of any kind has been attributed to a VTA dump valve on an impreza.

So in short, it's your car, have it how you want it! Just buy a decent rated one. I used a baileys once and had no issues at all, but loads of people have said they had issues with these, so I'd advise to stay away from them. Try HKS or forge, they seem to come recommended.

Good luck!

Subiehatch

Thank you BrownPantsRacing

Yes i had baileys myself and i dnt rate them as they are poorly made.

HKS OR FORGE

Thanks buddy.

**jay**

iTrader: (1)

Standard one releases pressure and also recycles it so un metered air is not lost causing fueling issues

scotty boy 80

iTrader: (5)

Pay for what exactly?

For him to put a different dump valve on if he gets fed up with it cos that's the only reason he'll change it, your argument is it comes with a dump valve so why change it, well imprezas come with a back box too but doesn't stop everyone changing that for sound

Subiehatch

Good point Scotty Boy.
We all like the rumble and the ooosh from the BOV.
I will order one tonight.
Have heard only good things about dumpvalves.

I dnt see the problem like i said its only pressure from the turbo coming out the bov when the throtle closes.

If they do damage,prove us wrong ??
Has it been proven before that its caused egine damage ????
Anyone proof ????

RAGGY DOO

iTrader: (1)

I'm getting a fluttering noise from the his induction kit when I lift off no need foot a dump valve

BrownPantsRacing

iTrader: (6)

If we're talking about mods for your car that you shouldn't do, then induction kits and cold air intakes are right up there above a vta dump valve. An updated panel filter is still good for 400bhp and the standard intake system has been proven very effective indeed. If you've fitted the induction kit without getting the car mapped then it's not a clever thing for your engine either.

My point is, there are worse things for your car than fitting a vent to air dump valve. Not a personal attack, just a contrasting point of view on dump valves.

alcazar

iTrader: (2)

My question to you was simple: will YOU pay if his following YOUR advice causes expensive problems?

No?

Then don't reject outright the advice of others.
It's his car, give him advice, but let HIM make his mind up. By all means tell him what it does, but to say that people giving the opposite advice are idiots, and infer that we somehow want to spoil the fun, is just childish.

alcazar

iTrader: (2)

You HAVE a dumpvalve.

When you take your foot off, it releases the compressed air from the turbo, but puts it back into the flow AFTER the MAF, so that you don't end up with metered air escaping.

The MAF has already metered the air, and THAT is what decides how much fuel the ecu adds. If the air escapes, (VTA valve), the fuel is still added, causing the car to run rich: pops, bangs, stuttering, borewash etc etc can, and do, all happen. Not all in every case, but there's enough evidence on here to say it's pretty common.

By all means put an aftermarket d/v on, but stick with a recirculating type. Forge are good.

Your car, though, your choice.

BrownPantsRacing

iTrader: (6)

Not really any point as the forge aftermarket recirculating dump valve is no better than the standard unit.

alcazar

iTrader: (2)

I was told by a very well regarded mapper that it was. hence my fitting one. I won't put anything on the car that doesn't add to it.