Dump valve noise - 1.2tce.

[theboydann]

This is not a clio question through the car has the 1.2 tce.

I have a new Twingo Gt. I have fitted a Bailey DV26 atm dump valve. Now on throttle it boosts and then releases as you'd expect, however on lower throttle, pootling about I am getting a resonation noise.

I am assuming that there is not enough vacuum to close the valve and its the sound of the turbo resonating up the pipe.

My questions are:

Am I correct in my assumption?
Is this going to cause issues?

Dan

 

[cam_hoof]

i have heard of this before, i think your right in what your thinking because the turbo is not working fully on low revs their is not anough vacume to close the valve thus causing it to resanate as said above,
i dont think it will cause any damage but dont hold me to that,
cam

 

[theboydann]

That's what I figured. As long as its not closing when it shouldn't and backing the pressure up on the turbo (which its not) I'm pretty sure Im alright.

Anyone else?

 

[cam_hoof]

if it keeps on doing it an you are worried about it try just opening the watse gate, imo it sounds better as well,

 

[-Leigh-]

My g/f has a Twingo GT and had a collins dump valve on it, and now has a forge dump valve.

No problems at low revs. Bailey dump valves are known for leaking boost, perhaps this is what is happening as it's not sealing properly??

I'd throw the Bailey in the bin tbh, and get a proper one.

(Oh, and I'll call you a chav like I call my g/f a chav! )

 

[cam_hoof]

(Oh, and I'll call you a chav like I call my g/f a chav! )[/quote]

this is the reason i did not put a dump valve on my ibza as i did not want to be branded,

 

[-Leigh-]

lol I'm only playing.

 

[diamond geezer]

i'll agree with the bailey ones, being shite, as said above bin it and invest in a forge one.

 

[-Leigh-]

I had a Bailey on my Punto GT and it leaked boost, and would stick on long journeys on motorways which would cause the car to stall. It was brand new too.

I don't rate them at all. Also, the Twingo GT runs tiny boost (8psi I have read), so make sure it is rated for that small amount of boost. The collins seemed to work fine, but the Forge did not, so I have had to get another spring from Forge so it will work. If the spring is too strong, it won't dump the air and can cause the turbo to stall.

 

[MillerLight]

Baileys dont get many good reviews on vxronline too.

 

[theboydann]

I have a dv26 on my Punto GT too (before I got sick of it). Yeah, I think I need one better rated to the car.

I know the car only runs low boost, Im hoping to change that.....

It's chavy but I had to do it as I'd had the NA clio for so long I missed it .

Dan

 

[The Chubby Pirate]

People will think its electric if its not japanese

 

[bmh.01]

I love my dump valve! . Baileys are pretty well renound to be shite from what i've read.

 

[-Leigh-]

Make a nice drink though.

 

[bmh.01]

Aye, very true.

 

[-Leigh-]

theboydann, if you get a forge dump valve, you want a fmdv004 dump valve, with a green (5-15psi) spring fitted.

 

[theboydann]

Cheers xzibit, I'll look into that.

What do you guys think is a safe amount of boost through these engines stock? I'm aware that the comp ratio is 9.5:1 so I don't want to go popping it.

Has anyone seen anything on the t'interweb about them?

I've seen a couple of foreign chip tuning sites which claim good power increases but there are no figures attached?

Dan

 

[-Leigh-]

Someone on renaultsport forum has got about 118bhp from theirs I think.

I'm not going to play about with the g/f's tbh, I don't like the compression ratio so I'm not keen on upping the boost.

She wanted a dv, and that's all that's going to be done.

 

[Neil G]

Baileys dont get many good reviews on vxronline too.

Definately crap, always run by morons who own Escort RS turbos

 

[phill172]

Imo dump valves are a waste of time, Iv got modified wastegates on the twin turbo e30 not only does it sound like a Group B rally car they dont leak or anything.....

However thats not always the easiest solution...

I know alot of people in the Jap scene who run the Hks Sequential and they really rate it, saying it doesnt leak and also doesnt stall the turbo (where you normally get that chatter sound from the boost hitting the compresser wheel)

There quite pricy but my be worth a go?

 

[DynamoDave]

I had a baileys dump valve on my old rover turbo (was on when I bought it) and it was poo!! It leaked boost and then the diaphram split soon after!

I replaced it with an HKS SSQV (mentioned above) and it was brilliant! The noise it makes is an acquired taste though lol.

 

[jayxx83]

Wouldnt say its worth putting a HKS super sequential on a 1.2 which is probably running 7psi max boost, it would be overkill.

As said before, the Forge are pretty good. Are you sure you dont need the bailey twin piston dump valve. Something to do with the airflow meter being before the turbo?

 

[ditz]

baileys tend to do that they are awfull.. its where at low revs its not making boost therefor is under vacum so it holds the valve open.. thats what you can hear.

forge are better, but dump valves are still a modifcation (in for sort of sence anyway) for people that dont know what they are doing

unless you are running 3bar of boost i'll eat my words.

twin piston dump valves are for when the airflow is metered before the turbo such as s1/pre 1990 s2 escort turbos or newer cars that have an airflow meter before the turbo...

i'd imagine that engine uses a map sensor like the 225 so it wont need that

 

[Brett]

Post a clip of the TCE with dump valve please!!!

 

[-Leigh-]

Are you sure you dont need the bailey twin piston dump valve. Something to do with the airflow meter being before the turbo?

DV26 is the twin piston, DV24 is the single piston.

 

[theboydann]

Bret_1990: It kind of sounds like an atm dump valve....hisses when you change gear. Nothing to post sound clips of!

Yes the DV26 is the twin piston jobbie.

Its coming off tonight as I think, like you said, its leaking boost...its intermittent on the acceleration....

Dan

 

[bmh.01]

baileys tend to do that they are awfull.. its where at low revs its not making boost therefor is under vacum so it holds the valve open.. thats what you can hear.

forge are better, but dump valves are still a modifcation (in for sort of sence anyway) for people that dont know what they are doing

unless you are running 3bar of boost i'll eat my words.

twin piston dump valves are for when the airflow is metered before the turbo such as s1/pre 1990 s2 escort turbos or newer cars that have an airflow meter before the turbo...

i'd imagine that engine uses a map sensor like the 225 so it wont need that

As far as I understand anything that uses MAF for air metering will overfuel with a dump to atmo DV in it as it will be dumping air thats already been metered and hence the ecu will inject fuel for air thats not there. Hence why you can only really use recircs with them if you give a damn about it.

The 225/1.2TCE uses map so it doesn't meter the air until its in the intake fanimold so as your dumping the air before that it doesn't matter. The 225 has a map sensor in the return hose from the intercooler before the throttle body so I imagine it'd see the pressure drop when a dump valve releases anyway, although at a guess that sensor is just there to make sure the turbo is making boost. Like the 2nd post-cat lambda idea.

 

[MillerLight]

u may find just replacing the pannel filter with a highflow one makes the standard wastegate much louder giving the same-ish sound. does on the corsavxr's

 

[-Leigh-]

^^ lol yeah.

Seriously though.

 

[ditz]

baileys tend to do that they are awfull.. its where at low revs its not making boost therefor is under vacum so it holds the valve open.. thats what you can hear.

forge are better, but dump valves are still a modifcation (in for sort of sence anyway) for people that dont know what they are doing

unless you are running 3bar of boost i'll eat my words.

twin piston dump valves are for when the airflow is metered before the turbo such as s1/pre 1990 s2 escort turbos or newer cars that have an airflow meter before the turbo...

i'd imagine that engine uses a map sensor like the 225 so it wont need that

As far as I understand anything that uses MAF for air metering will overfuel with a dump to atmo DV in it as it will be dumping air thats already been metered and hence the ecu will inject fuel for air thats not there. Hence why you can only really use recircs with them if you give a damn about it.

The 225/1.2TCE uses map so it doesn't meter the air until its in the intake fanimold so as your dumping the air before that it doesn't matter. The 225 has a map sensor in the return hose from the intercooler before the throttle body so I imagine it'd see the pressure drop when a dump valve releases anyway, although at a guess that sensor is just there to make sure the turbo is making boost. Like the 2nd post-cat lambda idea.

yeah that ones a boost sensor.. if its anything like the renault diesels (its a completely different kettle of fish but same sensors etc) they have an electronicly controlled boost regulation solenoid