the rally chatter sound comes from a dumpvalve right??
if so were can i get one from and how much am i looking at?

 

If you refering to the pchew,pchew noise(sorry!), yes this is a dump valve venting unwanted boost pressure to air and these can be had from almost any subaru modifier, but if you are asking about the backfire noise that sometimes sounds like a gun going off, this is called anti-lag and keeps boost at a minimum of 0.5-1.0 Bar so as to give no turbo lag when coming back on the power. This system is far more complex, and you wouldn't see much change out of 5K for a properly installed set-up that you would struggle to use on the road as it sets a very high idle

 

SO the sound of a dumpvalve cannot be altered just how ur car sounds?
i thought i heard one on a evo once it sound ace??

 

Do a search, its been answered many times before! While your at it make way for a big turbo,lots of boost, fmic,induction kit, full system! because its all of these things that make the sound you want!

 

I thought the Rally cars didnt have dump valves ?

 

They don't

 

The chatter noise is from the Wastgate venting to atmosphere,
Rally cars in WRC format do not have dumpvalves, as they provide no advantage to speed or performance. WRC turbo's are designed to work constantly under load..

 

Is it not the waist gate chatter that your thinking of edmy716??

 

its the fmic chatter ,

 

anti-lag

£1500

 

I thought it was the sound of the turbo stalling

 

i asked this question when i was on phone to guy at Jap-innovations..

the noise you hear is the air going through the pipes of a FMIC.

so u need a FMIC and higher boost to get the noise you require....

alot of money just for a sound i think!

 

The downside to anti lag is how it works, great for a rally car where parts are changed every 500 miles (due to wear and tear) but not good for a road car where you dont want to be replacing your turbo quite that often
Even having a mild version of this (if you can call any anti lag mild) will wear your turbo considerably quicker than you think, and as you havnt the resorces that a rally team has, ie money to spend on parts every few hundred miles, its not a viable option.

Tony

 

I thought it was waste gate noise too?

There was a small vid doing the rounds on here with a DBM impreza which had had some fettling and it sounded just like it.

Defo not a dump valve never heard the FMIC bit before.

 

surely if you took the dump valve off you would get wastgate chatter, But would this damage the turbo? What are the pros and cons or would it just make a nice sound?

 

it would eventually damage the turbo

 

how long is eventually? Getting various feed backs on this. Cheers for your help Sonic

 

it would depend on the turbo

my current TD04 std UK Turbo MY00 wouldnt last very long, dont know how long, but probably not that long, and im not willing to try it either

A friend has a bug eye with no dump valve, an external wastegate, FMIC, AntiLag,and a rather large garrett turbo, it sounds good, and his turbo will last a lot longer than mine would

 

i ran my td04 as a stop gap with no dumpvalve fora good few months

 

if you want chatter, then i would advise fitting an HKS mushroom filter.

i fitted this item to my car primarily as i had to junk the air box to fit my FMIC.

i fitted it prior to the FMIC and i got a nice bit of chatter.
after the FMIC was fitted i get absolutely tons of it!

sounds great!

do this and you won't be disappointed.

i have a forge VTA blow off valve also and this does detract slightly from the HKS in some ways. if you want the pure wastegate chatter, fit the std recirc (if you have a VTA blow off valve fitted now) and fit the HKS mushroom filter.

 

Turbosmart do an aftermarket wastegate that they say will give you that "rally car chatter"....dont know if it does,or not but have seen it advertized in japenese perfomance.

 

The chatter you hear on WRC cars is the wastegate chatter.

You won't get this noise on a road car unless you run a similar setup to the WRC cars which for most people is highly unlikely.

The noise that some of you are confusing for wastegate chatter on road cars is the noise of your dumpvalve. This is not the same. Although some DVs give a noise somewhat similar (especially when you have an FMIC).

My car with a front mount and VTA dv makes a "similar" kind of noise when you lift off at low boost but it isn't wastegate chatter.

Comparing road cars to WRC cars is like comparing yourself to Arnie Schwar.
You both have 2 arms, 2 legs and a head but that's where the similarity ends.
The WRC is VERY VERY different to the cars me and you all drive.

 

That would match my experiences with induction kits and HKS SSQV.

On my old GTIR I had a HKS mush filter and a HKS bov. When changing gear at somewhat low boost I could hear a chatter type noise but not much.

On my Impreza, I haven't got an induction kit due to MAF fears but I do have another HKS DV. Can't hear any chatter at all just the DV chuff.

Shame I can't find that short vid of the Impreza I was on about at its sounded really authentic.

 

The vid your talking about is probably Fuzz's, on here somewhere http://home.clara.net/andy.c/scooby.html

I seem to remember the reason for the chatter is running with no dump valve. Its the air coming back off the closed throttle eventually hitting the spinning turbo and causing the chatter. Depending upon the type of turbo you have this may not be recommended as it can shorten its life. That and some wastegate noise as well I guess.

 

Mine sounds like Fuzz's

 

lol at you lot.

Yes, no dump valve on mine, it is the air rushing back through the compressor wheel of the turbo when you shut the throttle.

That reminds me..... must do more video

Achoo

Andy

 

£1500 will only buy you a miram shaft for the turbo, before you even get the turbo rebuilt along with all the other parafanalia that goes with it, I should know, I work on 97 Group A Impreza with a ex-prodrive mechanic!