Can somebody post what brands/models there are of twin piston dumpvalves (I got an escort RST) ? I have bought the new DV36 on the fordfair, but the sound makes me feel gay....its a really tiny little whistel...

 

run about 2 bar of boost and it wont be a tiny whistle.

 

Didn't even know they did a DV36

DV24 is the single piston DV - will work but not the best for ERST's

DV26 is the twin piston one - best for ERST's

 

mines forge...



back off at 2.2 bar and its erm....... rather pronounced lets say lol

 

Fookin hell MATT.I bet when that thing dumps you think the engines cut out or holed a piston.Aint sen one like that before.Is there room under the bonnet for that

 

just

 

Don't bother with one mate from my experience the ERST never quite runs right with a dumpvalve on it. Lobbed my dumpvalve into my spares box and never looked back again.

 

dump the valve and bring on the chatter

 

joost....your not running enough boost.

 

this is the new DV 36 bailey dumpvalve

 

ps. do not buy it

the sound is really crap !

 

it might sound stupid but how do you get that chatter sound from an rs turbo

 

Who's for and who's against on dump valves.

Heard so many people say they are gay and rip the piss out of them and to be honest I haven't heard many turbo'd fords with one lately.

I had a FRST with one on and ok there was times I got a little pissed off with the noise when using the car alot, but generally i liked the sound, all part of owning a turbo in my eyes and encouraged me to boot it, My S1 doesn't have one and because it runs highish boost, i get enough chatter to keep me happy.

3 Spoke alloys = sh*te,

dump valves = personally i can't see the harm.

What does everyone else think??

 

i got a collins on my s1 and like the sound of that but now and then i take it off cause u cant beat the wastegate chatter especially on cossy's

 

mines running about 230 brake, so if i take the dump valve off it should make a chatter noise then?

 

The chatter sound is when you take of the dv. But what I heard that ain't to good for the turbo..

 

i know recirculating dump valves sound a lot like chatter but they only fit on certain cars dont they?

 

Yeah they do m8.wont fit a festa or escort fromwhat Ive been told. Wanna flog it? people say if your runnin high boost then you need a dump valve.is this true? I had a bailey which fooked up and wouldnt let the car idle when hot.They didnt wanna know.

 

i suppose it is better to haqve a dump valve with higher boost, i thought the dumpvalve keeps the turbo spinning and stops the turbo fom stalling before you come back on boost

 

 

Right... Time rto set a few things straight for you guys.

What "chatter" actually is, is turbo-stall. It is found on most tubo cars not running dump valves and noise-restricting air filters. What it actually is, is when you lift off the throttle or change gear, then throttle butterfly snaps shut stopping the charge air you have already built up from entering the engine via the throttle bodie. This air has to go somewhere, and without a vent (dumpvalve) it is forced backwards through the charge air system and out of the only other exit - the air filter. To get out of the air filter it msut pass thru the turbo. Now the turbo is still spinning away, so the air travels back through the blades, effectively "stalling" the turbine (blades spinning one way, reversed air makes em spin other way) The noise you hear is at this point, and is the charge air being " chopped" by the turbine blades.

With a car running a d/valve, you don't really get this "chatter" as the majority is vented out of the dumpvalve to atmosphere (eg: your Bailey DV24/26 etc, and any one that makes the "p-tish" sound

Re-circulating Dump Valves

No sorry, they don't. As their name suggest's, re-circ d/valves re-circualate the escaping charge air back into the charge air system, usually before the turbocharger, which aids in a tiny version of anti-lag really (by forcing the air back in before the turbo you keep it spinning for when you come back on the throttle)

But this doesn't make a "chatter" noise. In fact it doesn't make any noise, and is virtually silent. Manufacturers use these d/valves for this very reason as regular Joe doesn't want nor is interested in "P-TISH!" or "cha-cha-cha-cha" noises. It also helps in the long run with turbo life.

Which brings me onto the next point - prolonging turbo life. Most say you HAVE to run a d/v otherwise the turbo will explode in millions of bits. Not so. YOu only really need d/v's on cars running fairly large ammounts of boost in ratio to the turbo size (determined by ammount of air the turbo can flow)

Your T3 turbo'd ERST doens't really need a d/v till you running more than 18psi. I would still run one well before this, jsut as it will assist in prolonging the life of your unit.

One last note on chatter. Cossies can chatter, Fiesta turbo's can chatter, but on the whole, Escort turbo's cannot. Why? COs Cossies and FRST's turbo's vent directly into the air filters, where as the ERST's turbo have a metering unit between the turbo and the air filter. With the throttle snapped shut, the flap on the metering unit is also shut, preventing any charge air from exiting back out of the air filter. Cossies and FRST's (as with most turbo cars like this) will chatter louder with the sound-restrictive airbox removed in favour of a cone.

Hope this is of some use to everyone and dismiss a few myths and straighten a few fatcs

 

good posting

 

 

Thrush,good write up mate.very informative.One thing i wanna know is why,having fitted a -31 actuator and chipped ecu on my escort rs2 it chatters more than my missus could posibly do in a day?

 

There are the odd exceptions to the rule with ERST's in regards to chatter. I know of a couple that do chatter all day long, even at jsut 9/10psi of boost. The only explantion is that the metering unit (between turbo and air filter is on the way out and not working rightly. Don't hold me to this, as it is not proven, but when they are doing what they should be doing, with the throttle shut (ie: your foot off pedal) the metering unit should be shut too. Inside the metering unit is a big round plate on a pivoting arm. Air being sucked in from the air filter pushes the arm down, thus making the plate go down too. When charge air has to find it's own way out with throttle snapped shut, it naturally goes back through the charge system. But it should not be able to escape thought the metering unit as the plate only opens one way and the escaping charge air will be traveling backwards. The only thing it can do is push harder against the plate, and pushing from under the plate will definitely close it.

So to creat chatter you have to have air pass through the turbo and out the air filter for you to hear it. It is not possible for this air, once it has gone back through the turbo to escape via the metering unit, if the metering unit is working properly. If air IS getting out past the metering "flap" then there must be something wrong with the metering unit for air to escape from it.

If you get what I mean

 

 

That is definatley something I dont wanna hear.Bloody hell its about the only thing I havent replaced

 

Cheers Thrush, now this is a great explanation !!!!

 

so is there a difference between waste gate chatter and turbo chatter. i was always lead to beleive the chatter was from the turbo stalling but several people have said it from the wastegate fluttering.
also i could get very light chatter from the ke jetronic systems. i found if u easy of the throttle but not full close it the flap stays open enough to let some air out. either that or my metering unit is fudge like u said

 

Well explained Thrush

 

Wastegate chatter does not exist. Pure and simple. It is purely a term fabricated by those who don't know and mostly the motoring media.

Pet/Mr Cossie 4x4 -

Starturbo - As I said, don't hold me to this as it is not proven. But if you think about it logically, and understand how the system works then it does not make sense that in a perfectly working system chatter can occur (in an ERST with KE-Jet I mean)

 

you seem to know your shit