Dump valves...

zozzie_9t9 · Post by **zozzie_9t9** » Tue Apr 17, 2007 12:25 pm

Been thinking about this recently...

Having seen (and heard!) various cars recently with atmospheric dump valves, I do wonder if I'd like one for the ti

It's one of those things I've wondered about for a while, and if one came up at the right price on eBay, I might be interested...

What would worry me is that the noise would become annoying in normal driving... Is this the case?

Squaddiemodo · Post by **Squaddiemodo** » Tue Apr 17, 2007 12:29 pm

depends on the DV mate, i have a bolt on type, that sounds good, but isnt intrusive at all.

C2K · Post by **C2K** » Tue Apr 17, 2007 12:31 pm

I never really got annoyed with mine over 2.5 years, and that was a single piston "ptsch" kind of DV.

Unless your definition of normal driving would be floor it, change, floor it change you'd hardly notice. Get a bolt on for the T25 if you're worried, as no pipes need cutting then so you can always revert to the OE recirc.

Null_Byte · Post by **Null_Byte** » Tue Apr 17, 2007 12:54 pm

No, they sound great IMHO, under most normal driving they are pretty silent on a stock engine. Its only when really giving it some beans you will hear it when you change gear.

As has been said, get a bolt on one, then if you don't like it you can swap your OE one back and sell it on for about what you paid for it (prices are always good on DVs)

inky · Post by **inky** » Tue Apr 17, 2007 1:22 pm

I had a bolt on type piston type dump valve on my ti when I first got it and for a short while it was quite fun - but once the decat was on and the boost turned up a little it became embarrassingly loud for my liking! It was replaced with a standard recirc valve with one of those fancy diaphragms and an uprated spring and I couldn't be more happy with it now. It is still audible and IMO sounds much nicer.

victor3 · Post by **victor3** » Tue Apr 17, 2007 2:42 pm

Sorry, chaps. They're all a bit 'chavvy' for me!!

216si · Post by **216si** » Tue Apr 17, 2007 4:12 pm

have had a single piston baileys, twin piston baileys and also a forge diaphram one, all got boring tbh, so i have removed the dv alltogether and have been running compressor stall for the last 3 month, much better sound and not a in your face

Roger Red Hat · Post by **Roger Red Hat** » Tue Apr 17, 2007 5:01 pm

got to agree with victor3 on this one..

not really any major need for one either..

reminds me when my mate put one on his TD306, wich made me laugh a bit

Dom · Post by **Dom** » Tue Apr 17, 2007 5:09 pm

What is compressor stall...?

Was this not one of the things that was supposed to be bad for the blades, or am I getting mixed up with something else..?

Dom

zozzie_9t9 · Post by **zozzie_9t9** » Tue Apr 17, 2007 5:18 pm

Thanks for the replies lads!

roger red hat wrote:not really any major need for one either

I know that! But I rather like the noise

And I reckon most people fit them so people know they're driving a turbocharged car

I'll keep an eye out for a bolt on one - that appeals, cos if it does annoy me, I can easily go back

roger red hat wrote:reminds me when my mate put one on his TD306, wich made me laugh a bit

You mean I shouldn't fit one to my 620iSD then?!

calibrax · Post by **calibrax** » Tue Apr 17, 2007 5:25 pm

Dom wrote:What is compressor stall...?

Was this not one of the things that was supposed to be bad for the blades, or am I getting mixed up with something else..?

Dom

No, you're right. Compressor stall is when you lift off the throttle and the pressured air on the inlet side has nowhere to go except back through the turbo blades, and it makes a chattering noise as the blades cut through this wall of air. It's the noise often referred to (incorrectly) as 'wastegate chatter'.

At high boost levels it can certainly damage the blades, but at 12psi, it's generally not seen as a problem. Sounds cool too

Roger Red Hat · Post by **Roger Red Hat** » Tue Apr 17, 2007 5:27 pm

the noise you hear rally cars make sometimes..

sexy noise :p

zozzie_9t9 · Post by **zozzie_9t9** » Tue Apr 17, 2007 5:29 pm

calibrax wrote:No, you're right. Compressor stall is when you lift off the throttle and the pressured air on the inlet side has nowhere to go except back through the turbo blades, and it makes a chattering noise as the blades cut through this wall of air. It's the noise often referred to (incorrectly) as 'wastegate chatter'.

At high boost levels it can certainly damage the blades, but at 12psi, it's generally not seen as a problem. Sounds cool too

Isn't that how red rover had his ti?

Roger Red Hat · Post by **Roger Red Hat** » Tue Apr 17, 2007 5:37 pm

no i mean.

his was purly cos he thought it would give him an extra 60 bhp etc

he also had the whole blue led washers and shite..

zozzie_9t9 · Post by **zozzie_9t9** » Tue Apr 17, 2007 5:41 pm

roger red hat wrote:no i mean.

his was purly cos he thought it would give him an extra 60 bhp etc

he also had the whole blue led washers and shite..

I was joking! I don't think a loud dump valve would have quite the same effect on my diesel!

inky · Post by **inky** » Tue Apr 17, 2007 7:49 pm

With regards to the compressor stall - has anyone run one a standard T25 like this for a while without any ill effect? I'm not going to be running more than 12psi on my vitesse so am interested to see if it would be ok long term.

Bob SLi · Post by **Bob SLi** » Tue Apr 17, 2007 9:35 pm

i have no idea what type mine is but i love it, i love the noise.

noting below about 2.5k rpm but when giving it the beans it gives a nice crsip ptshhh. i do love doing it when passing pedestrians, it amuses me greatly!!!

MGJohn · Post by **MGJohn** » Tue Apr 17, 2007 9:55 pm

When I bought a 'sickly' 620ti off ebay for relatively little money, lifting the bonnet revealed a shiny new blue Forge DV replacement! Until then, I was, repeat was, in the Victor3 (Mental Maestro) camp ... no noisy DVs on my turbos...

Anyhow, fitted it to my V-reg car to see what's what and guess what, I like it for the following reasons. It is NOT obtrusive to the driver at any time ( although my hearing is not what it was on account of age wear and tear ) but, it IS noticeable to other road users when using the performance of the car.

What I most like about it is when shall we say 'matching strides' with some non-Rover driving road user who obviously and quite mistakenly fancies his (or, sometimes her) chances, as soon as you change up around 40 in 1st or 60+ in second, when they hear that old Whooshtiishh, many tend to throw the towel in on a WTF basis. I'll never tire of that experience.... only today, laddo in his superior Alfa given the WTF it's an old Rover treatment ....

Funny old game folks and their cars.

Post by **Punx0r** » Tue Apr 17, 2007 11:54 pm

I've got no DV on my T28 but can't say I've heard any noises that I'd call compressor stall. It's pretty silent like the T25 was. Maybe I've just got a huge (quiet) boost leak

114gta · Post by **114gta** » Wed Apr 18, 2007 1:43 am

Punx0r wrote:I've got no DV on my T28 but can't say I've heard any noises that I'd call compressor stall. It's pretty silent like the T25 was. Maybe I've just got a huge (quiet) boost leak

My DV stuck closed and i was getting comp. stall on my T28, i could hear it but it was very quiet and my car runs 1.2bar.

C2K · Post by **C2K** » Wed Apr 18, 2007 7:29 am

MGJohn wrote:only today, laddo in his superior Alfa given the WTF it's an old Rover treatment ....

benji_ · Post by **benji_** » Wed Apr 18, 2007 8:02 am

Mine has a Turbosmart Megasonic on there and it sounds great. Combine that with the chatter of a GT28R and it sounds fantastic. Just by moving the air filter closer to the floor the whole sound of the car has changed! It sounds like NOTHING I've ever heard before! The spool up from the turbo is AWESOME, it's so loud! Then you get a MASSIVE chatter from the turbo and then the dump vale goes PPPPPPTTTTTTIIIISSSSSSHHHH and change gear and do it all again!!

Gotta luv turbo charged cars

Post by **agw_01** » Wed Apr 18, 2007 9:42 am

I don't have an atmos DV, mine's just made up of the OE re-circ and a cone air filter... and boy oh boy is it loud

It doesn't sound as good as proper chatter, it's a bit more metallic... and when driving through town I do wish it would shut up. But on the way home last night I put my foot down on a nice long straight and changed gear at around 5500rpm in a few gears... sounded soooooooooo nice!

Turns lots and lots of heads too, and the turbo spool is just immense.

E_T_V · Post by **E_T_V** » Wed Apr 18, 2007 9:51 am

The missus car has both an open cone and an atmoshperic DV. Its quite loud, but I don't care. It drowns out the squeaks at least.

victor3 · Post by **victor3** » Wed Apr 18, 2007 10:27 am

If I wanted a loud car, I'd chop my exhaust off!!

All this 'ker-choo' stuff is just to impress the pedestrians!!

Stealth is my wealth..... :!:

shen · Post by **shen** » Wed Apr 18, 2007 10:38 am

I have a bolt onto turbo type and in my opinion its a bit of an odd thing having a DV at all for the noise purposes...heres my 20p worth

If you're driving casually you wont hear much but a deep sigh on gear change.

If you're flooring it and changing gears right you hardly hear it as the hiss is so quick before the turbo is winding again.

Best thing about dump valve is that if you want it o dump and whoosh you can on demand pretty much and if you dont you dont need to

so passing other cars and showing youre turbo'd or just generally grabbing attention is at your discretion.

zozzie_9t9 · Post by **zozzie_9t9** » Wed Apr 18, 2007 10:50 am

victor3 wrote:All this 'ker-choo' stuff is just to impress the pedestrians!!

And what's the problem with that!

I think it now now a case of 'I want one' now!

The description which John gives sounds like the sort of thing I want!

C2K · Post by **C2K** » Wed Apr 18, 2007 12:40 pm

victor3 wrote:All this 'ker-choo' stuff is just to impress the pedestrians!!

Depends if you're still at the right age. I find it useful for making the ladies turn round so you can see if the face belongs on crimewatch.

Also makes all the chavs turn round looking for the Ashtray or Impretzel, and get extra confused by the sight of a Rover.

victor3 · Post by **victor3** » Wed Apr 18, 2007 3:42 pm

C2K wrote:
victor3 wrote:All this 'ker-choo' stuff is just to impress the pedestrians!!
Depends if you're still at the right age. I find it useful for making the ladies turn round so you can see if the face belongs on crimewatch.

Also makes all the chavs turn round looking for the Ashtray or Impretzel, and get extra confused by the sight of a Rover.

Don't need a DV for these:-

Use the horn (either audible or visual, if you want to risk it

).to make ladies turn around

Confuse a chav by asking him the time and insisting that the reply does not include the words 'hand', 'big' or 'small'!!