Just found this on youtube.....I was under the impression TDi Turbos were non-atmospheric?

If this is true and can be achieved - at what price does it come?

Danny

A screamer pipe direct to the wastegate.

No can do on the fabia vrs, as the turbo it has is a VNT turbo and doesnt have a waste gate.

Personal opinion i think it sounds rubbish, and i dont think his turbo will last long making those kind of noises~!

Apparently this one is off a Fabia vRS....

I know the sound isnt as great as a

petrol turbo'd car, but I quite like it.

Danny

Before I snort with disdain at these chumps and their lack of knowledge, can someone who knows tell me if this comment (off youtube) is cobblers or not?

its a valve that releases the air from the turbo when you close the thortle in a gasoline engine. preventing the turbo pipe from blowing.

BUT

since diesel engine DO NOT have a thortle, this valve is useless. dont put a BOV on your dieasel.

I was under the impression that a dump valve/wastegate was there to keep the turbo spinning when you took your foot off the gas by preventing the pressure imbalance from stopping the turbo trying to go backwards, am I wrong?

Save your money mate. This sounds better than both of them...

YouTube - blow off valve duck call

LMAO - That IS pretty funny in all honesty.

Danny

The Derv Doctor is the one you need to be asking.

He can supply and fits them.

If you search on dump valves you will find a plethora of information and opinions.

However I recently wrote a post over on the Fiat Forum (Punto section) in reply to a post about fitting one to JTD. Here is the jist of it (Please appreciate I wrote this for the Punto forum although the same will apply to the VRS as it is also fitted with VNT);

"In your petrol engine your turbo is spinning at say 100k revs.... suddenly your throttle closes, and turbo is still spinning due to inertia... consequently the air has nowhere to go because the thottle plate is shut... so the dump valve opens and allows this air to escape to the atmosphere(or back into the air box if a recirc is fitted)... this has the benfit of allowing the turbo to keep spinning in a partial vacuum for a longer period of time, and therefore takes less time to get back up to speed after you reapply the throttle..

On a diesel engine it isn't required because there is no throttle body, so the air doesn't get trapped like it does on a petrol engine.... in fact the excess air actually reduces the emmissions output from the engine and also has a mild intercooling effect on the combustion chambers

You can get electronically actuated valves for the JTD but TBH the only thing you will get out of it is a Noise and it might actually adversly effect the performance. A DV cannot increase performance. There is nothing for it to do other than go PSCHTTTTTTTT and unless it's perfectly actuated and it gets it spot on it will loose you boost pressure.

The boost pressure is generally highest on a diesel when the accelerator is on the floor and the engine is as max power, just before a gear change. If a dump valve is set to relieve the pressure just below max boost, it will sound similar to that on a petrol engine, but it will be dumping air while the engine is on power, not when the accelerator has just been released. All it can do is make the turbo less efficient. The wastegate tries to control the boost pressure and that will just increase the exhaust back pressure if the pressure is being dumped by a dump valve.

Now also figure in the fact the fact the JTD turbo is a VNT (GT1749V I belive if it's the 85bhp version) and this works works by adjusting the gas throat section at the inlet of the turbine wheel in order to optimize turbine power with the required flow velocity. At low engine speed and small gas flow, the turbocharger reduces the throat section, increasing turbine power and boost pressure. At full engine speed and high gas flow, the VNT increases the throat section, avoiding turbocharger overspeed and maintaining the booster pressure required by the engine. How do you think sticking a remote control hole (Which is what the valve is really) in the system will effect this? It will defeat the object totally and all it will do is work against it.

I would really like to see a dyno run of a standard car and the one fitted with a DV back to back. I think the run with the valve would show early boost loss and spikes where the VNT is struggling to compensate. The only way it could be perceived to increase performance is if you mapped around it which is pointless because you might as well have just mapped a standard engine

It's an expensive toy and about as useful as a catflap in a submarine"

There may be someone with a deeper knowledge than me who will pick a few holes in my understanding of VNT's but I am not that far off the mark.

If you really want that noise there is also One of these Evil pieces of equipment

But then you end up with a car that goes like this

It's down to you what you do, it's your car and if we all followed the marker then we are all doomed so just you make sure you are happy

I was an idiot and bought one for the sound. I still like the sound but the car was noticably slower with it on.

Utter rubbish, don't bother.

It's an expensive toy and about as useful as a catflap in a submarine"

-That's a great phrase.

- Listen, I think what people are trying to say is... Save the money and spend it on somthing that will actually be worth while towards your car.

It is your choice but to be honest - You only have to watch the video to see 'The type off people' who have that MOD on the cars...

I was an idiot and bought one for the sound. I still like the sound but the car was noticably slower with it on.

Utter rubbish, don't bother.

You just said in three lines what it took me an hour to write

You could buy a hell of a lot of fake Burberry clothing down the market for what that mod would cost!!!

Ha ha.....thanks for all your feedback guys....especially nickl0......I aint gonna bother pal - thanks again to all.

Danny

@ Decron - Lol, I found out by spending almost a week's wages though! Doh!

@ dcackers - no probs! However, if you change your mind I have a beautifully made (and it really is, just a shame it's pointless) Forge diesel dump valve kit for sale! Some idiot on ebay will buy it when I can be bothered to stick it on there lol.

Clearway, you beat me to it!!1 ;-)

Perhaps some neons as well :p

YouTube - Bull Horn Video Much more entertainment than a fake BOV