Dump Valves

[Pixel]

Hey guys,

If you didnt already know, I have a Peugeot 206 HDi 2.0 D-Turbo, you should know this as my signature makes it painfully obvious. I want dump valves for my car, they are very common on diesels with turbos right? I want the sound anyway and my mate said it could cost me £350 in total whilst a different mate said it would cost £50 or less.

I just want that sexual hissing sound between gear shifting.

Can you help me out?

Pixel.

[HDi fun]

You can get a kit that makes dump valve noises via under bonnet speakers for fifty quid.

I never thought that a dump valve was applicable to a diesel engine. Diesels run on excess air (no throttle to restrict air intake, like a petrol car has) so no need for a dump valve.

When you lift off the pedal in your (diesel) car all you're doing is telling the ECU to stop fuelling. Air flow is never changed, so your turbocharger will spin up equally quickly in the next gear. There's no need to 'dump' an air charge as it's always available given the nature of a diesel engine.

PS:- HDi Peugeot diesel units sound pretty nice anyway, they hiss and make air intake noises under acceleration that are quite sexy (if cars' noises can be as such)

Dump valves have a use in off-road petrol fuelled rally cars. To me they sound like someone trying to flush a toilet inorder to dispose of an unrequited turd and an over size sanitary towel. Not so sexy, really.

And, with a diesel turbo, no need for it.

[oceaness]

Might look a little silly with the big HDI badge on the back when your car starts sounding like a petrol

[HDi fun]

There is that. Badges can be removed though. And diesels still sound like diesels outside when they're sitting still (with the engine running, obviously).

[vr1066]

What is the actual purpose of the of a dump valve(s), is there more than one.

Yes thats right, the newbie siren just went of for that question :P

[HDi fun]

Dump valves allow the turbo(s) to carry on spinning in free air when the throttle is closed during gear changes. It helps to eliminate turbo lag. If you're a race driver you probably won't need 'em as you'll keep the throttle pedal flat down (against the rev limiter) during changes anyway.

Clearly this is more economical if your sponsor is paying for your tyres, clutches, and fuel.

Dump valves don't really have a place on the road with sophisticated engine management systems.

But they do make a good sound if you like that sort of thing.

[vr1066]

Thanks for the answer.

Can I assume that you wouldn't fit them if your not running a turbo or do ppl just use them for the sound?

I think I'm more interested in the engine noise than the dump valve. Although I'm curious about them as I've heard them mentioned a few times.

[HDi fun]

Dump valves had a place in Group N Rally cars back in the late 1980's. As for road use; technology has moved on. Engine management systems take up the slack, a good re-map can make all the difference.

Yes, they do have a purpose, but no so much as they did a few years back.

Dump valves belong in 1984 Fiat Uno Turbo's.

[Pixel]

But the sound is sexy :P

[HDi fun]

You can't use a dump valve on a car without a turbo - there's no point.

You can get a kit that has under bonnet speakers to make dump valve noises.

But it sounds so silly when you're going up from 3rd to 4th at 35 mph.

You'll never hear them on a race car as the engine's doing 8000+ RPM when changes are made so it gets obliterated.

Still, if you really want to, why not?

Cheers,

P.