fiestaturbo.com

[Bash]

Ok what do dump valves supposed to do? They increase Bhp or just make engine sound louder? Would it sound sweet with a full exhaust system in as well as a dump valve?

I have an SI and im close to gettin a Black Diamond 3 full exhaust system with a 3 and half inch tailpiipe.
Thanks

[rs van dan]

no they dont add bhp they protect your turbo by releasing the boost when you back ot the throttle if you have a si you cant fitt on

[Silver2iReplica]

would sound kwality if ya could get it to work on ya injection car!!!

they are silly things really just sound silly and waste fuel. but i love em!

rs cossie drove past an me bird goes "why is that car squeaking" so i spend the next 10 mins explaining 2 her wot a DV is!!!

hhhhmmm woz wonderin if ya can fit em 2 a turbo deisel n e 1 no???

[Mr Jungle]

WEll i read in Max Power onnce you can NOT get a Dump valve for a Turbo Deisel cause they work diffently !!!

Shame i know, but i dont give a poo cause i dont have a turbo

[UHF]

Outa luck m8tey, no turbo, no dump!

[Excursion]

go out and buy a dump valve today

**comes with free membership to the boyracer gang**

[Bash]

b0ll0><!

nah its an SI, so no dump valve for me.
People at work say your car will sound like some buses when ya change gear. Be reyt, ill do without.

PS Does the bigger size tailpipe produce are more deeper sound??
(i like my SI to have a beefy sound )

[Silver2iReplica]

Mainly yes, but in theory no.

the tailpipe size will not change the noise level, though big ends are mostly ones that make alot of noise, Ive got a Peco bb4 meanin its got a 4" tail pipe, this is total 'crap though, cus if u look at it, it goes down to a pretty small size only about 1 1/2 - 2 inches. though it is a nice sound and looks like a big tail pipe. twin dtm is quite good apparently, though i couldnt get em for me car, so u mite neither.

ask around who's got a nice sound outta their Si a copy em!

[Project]

60mm exhaust bore and straight through silencer boxes with any tailpipe will sound lovely

[elm_us]

that would be very loud m8 lol

i want a DV arrrrrrrrrrr i realy do i love the sound of them and i drive a lorry when ever posable as they have 16 gears and the gear changeing never ends

[Fezzy Turbo]

On 2002-04-09 19:04, Silver2iReplica wrote:
they are silly things really just sound silly and waste fuel. but i love em!

How did you work that out how does a D/V waste fuel

[MadcatCraig]

A dump vlave releases pressure in the charge carriers when you let off the throttle to avoid the air going back and spinngin the turbo blades in the opposite direction to normal ! Doing this allows the turbo to carry on spinning when you let off the throttle so when you floor it again the pick up will be quicker so in theory you can get back on boost faster.

If you dont have one and you have a cone air filter you will get chatter which is still quite loud but not as loud as a dump valve.

Turbos only im affraid and you can get them on turbo diesels as my mate has one on his Renault 19 turbo diesel.

[sunnyFRST]

All dump valves are gimmiks unless you have a HUGE turbo where a DV is really needed (to protect the large blades from shattering on high boost on back presure). Infact having a DV with a T2 or T3 turbo would slow the car down when comming back onto boost.
However this is not 100% true as there are some dumpvalves that overcome this problem and do what they're really supposed to do(they are only worth buying if your car has say a T4 (or larger and if you can afford them as the proper jap ones aint cheap. )

Sunny.

[Silver2iReplica]

On 2002-04-10 14:55, sunnyFRST wrote:
All dump valves are gimmiks ...

...Infact having a DV with a T2 or T3 turbo would slow the car down when comming back onto boost.

as i said sound silly and waste fuel!

but i aint dissing them, as i can assure u if i had any sort of turbo on my car, it would def have a DV!!!

[Excursion]

well said Sunny

[rs van dan]

if i had to have one i would have a recirlating one like the rally cars

[Excursion]

audi's come as standard with a decent recirculating valve which can be amde to fit a fiesta - best route for low boost

big boost and its a gredy or apexi blowoff valve

[chumkila]

i cant wait to show u guys pics of a certain Audi in the making! It'll literally take the WORLD by storm!! but i'm not permitted to take pics yet.

[Jags]

Yeah the Audi left me gobsmacked

[Fezzy Turbo]

Cossies came with a re-circulating DV to.

Silver2iReplica...........what do you mean DV waste fuel ??

[gooner boy]

i heard that if you take your car to ahmed bayjoo himself, he recommends you should take them off as you can lose power, as my mate with ERST s2 got chip from him. goes it just makes a noise and thats it.



<font size=-1>[ This Message was edited by: gooner boy on 2002-04-12 09:17 ]</font>

[turbo man]

DV are for slow gear changers, unless you pipe them up to your "anti-lag" system instead of the by-pass valve, then watch your engine go tearing off down the road leaving you for dust as it rips out the engine bay when you release the clutch! But seriously, if you let the boost build up without the DV you get "extra" boost when you put the gas back on and accelerate faster, mint. Unless it builds up too much and then you get blade "chatter". This is what happens if you NEED a dump valve. Basically the pressure stops the compressor spinning and a "chatter" or "cooing" noise comes out the air filter, this is when you know you NEED a DV. Otherwise they are just there for the noise.

[Bash]

lol what a thread.

Shame i cant get a ruddy DV!

I wont more p0wer! cheapily

[Fezzy Turbo]

Dump valves make a noise and release any back pressure from hitting the compressor wheel of the turbo.

Turbo man....if you get any turbo chatter it does not mean you have to get a D/V. You just need to stick a cone filter on a FRST and it will chatter.
You dont get "extra" boost without a D/V, it's just that there is no need for the turbo to "re-fill" the charge carrier, I/C and pipes that have just been emptied by the D/V releasing the back pressure.

and could you explain how you connect a D/V to anti-lag

Gooner boy...... a lot of tuners will ask you to remove the D/V, it might not loose you power but it effects the pick up speed of the car, as i explained to Turbo man.

[EvilFranky]

I still get turbo chatter and i have a dump valve...

[turbo man]

The turbo shouldn't make any noise at all, if it is then it is getting pulses pressure waves. Maybe your DV isn't letting out enough air, but one BIG problem is cone filters. These are no good for turbos, free flow panel filters are better.

You will achive "extra boost" without a DV as for the split seconds that take you to change gear the turbo doesn't stop spinning does it, no, but the engine is closed off and not taking the pressure away, so pressure builds up to high than normal. Yes the wastegate will open to reduce the amount the compressor turns but its not an instantaneous thing.

In an anti-lag system there is a bypass valve that lets air through the engine when the throttle is closed, ie when you change gear. Fuel is put in and the ignition is retarded really really far, so when the exhaust valves open thats when it sparks, so the expansion occurs in the exhaust manifold and winds the turbo up. Using the DV as a bypass it would be able to wind the boost up indefinitly the engine would be effectivly "removed" from the equation. Systems like this are used to run REALLY low compression engines on comercial vechiles, lots and lots of power, but fuel is cained at low rpm, so they obviously run at high rpm and use system to get into the boost area.

[Fezzy Turbo]

Oh no not the debate about cone filters again i have had a cone filter for a long time and it has done no harm to my car and it still made good power when rolling roaded.

I also get some chatter with me Collins D/V, that is more due to the D/V not opening quick enough.

Turbo man.....i think you will find that the compressor wheel can stop with the back pressure, thats why D/V's were developed. This back pressure can "stall" the compressor wheel as it is travelling in the wrong direction the compressor wheel was pushing the air. On big turbos this can cause too much stress on the compressor baldes and have caused them to crack. The D/V releases the back pressure allowing the compressor wheel to keep spinning in its proper direction. But the turbo then has to "re-fill" the areas that have lost the pressured air, thats why you can loose some performance on take off.

[Gaz7]

Sunny had it spot on with what he said, i second everything he said. As for cone filters, i agree with Greg, there is no big problem, its just each to their own individual taste, i have mine purely for the fact that i like the chatter noise it makes.

Gareth

[Ian C70T5]

I agree with Fezzy.. HOW does a Dump Valve WASTE Fuel??? News to me..

Or does petrol run through the boost hoses so that when i demp it lets all my fuel out at once.. NO WONDER i keep running out of petrol..

If you could fit them to NON turbo cars i would REMOVE mine as it would be common and pants.. I've been considering fitting a recirculating D/V..

And also once again Sunny is correct, they do nothing unless you are running a large turbo with MASSIVE boost.. us mear mortals only have it to sound nice

[Joris]

I suggest meo786213565461468351464854615649 to leave this tread and all the others to read sunny's reply

[Fezzy Turbo]

LOL @ Joris

You were thinking the same thing as me