sagan

I have a forge BOV on my classic but i really love to have this sound...

Can you tell me what BOV does this discharge sound?

YouTube - Subaru Impreza WRC98 in action on French tarmac - with pure engine sounds

cheers!

dazdavies

iTrader: (22)

That's a sound of having NO BOV.
Cracking vid too!!

midnight

iTrader: (10)

F***ng awesome video,no signs of any dump valve on that motor,he was going to fast to hear it anyway lol.Saving that vid straight to my i phone ,impressive - very impressive.

sagan

so i just remove it from the IC and like place a metal plate to plug the hole and i get this type of sound?

what consequences does it have to remove the dump?

sagan

anyone knows?

0ctane

iTrader: (1)

That actually sounds like an HKS SSQ dump valve to me.

Blocking it off isn't a great idea as when you lift off the excess boost has to go somewhere. If it is not vented to atmosphere or back into the intake it has to go backwards through the turbo. That means your turbo which is spinning at 100000RPM now has to stop almost immediately... not good for the longegivity of the turbo.

There is a mod which a lot of us have done to get that lovely turbo chatter. Go to your local store and buy a cheap soft plastic lunchbox or similar. Remove your dump valve and use the gasket as a template to cut out a solid piece of plastic from the lunchbox lid. Drill a couple of 5mm holes in the middle of the gasket to let some of the air through (you may want to experiment with different quantities of holes to get the sound you like). Replace the dump valve using this plastic piece as the gasket.

Quick, easy, reversible and sounds awesome!

Splitpin

No. Even if you remove your dumpvalve it won't make that sound, because you're (presumably) not driving an Impreza WRC. So your engine doesn't have the same induction tract, same antilag strategy, the same size turbo and the same amount of boost pressure, and you don't drive it on the limit all the time. All those things, and more, are what make those cars make that noise.

On a roadcar with DV delete you'll, at best, get a pretty anaemic/pathetic sounding version of it, and you won't hear it very often, unless you drive your car absolutely flat out everywhere.

Possibly none, or possibly a broken turbo, or if you're really unlucky, a broken engine. You haven't told us what car you have so it's impossible to give you any more info than that.

Plenty of people have asked this question in the past so clicking Search will tell you a lot more.

sagan

lol great ideia!
so using the hole i wont seal totally the ic circuit...

i'll have it a go with a piece of plastic or some rubber (to seal a bit better).

i have a prodrive classic impreza.

Splitpin

If you have, as per the pictures on another thread, a 1999 or 2000 model year car, you would be well advised to not try this.

Deleting the dumpvalve causes air pressure waves (the noise you hear) which travel backwards up the inlet tract. The airflow sensor used on 99/00 can be very quickly damaged by the vibration that results from being buffeted by these pressure waves. If you're not already aware of it, the consequences of a damaged MAF sensor are, if not picked up early, are often a thread on here asking how many thousands of pounds (euros) it'll cost to fix your blown engine.

If you want your car to sound like a WRC, the safest way to achieve it is to burn the sound of that video you posted onto a CD and play it on your car stereo.

Splitpin

Yet the idea you're suggesting is still blocking it off - albeit partially rather than completely.

That isn't quite what happens. The turbo doesn't "stop", but it certainly does get a big shock.

Hmm. You've just said that blocking off the dumpvalve is bad because of <stuff>. You seem to be saying that the "lunchbox mod" is somehow better because it doesn't block it off. That's clearly not quite what's happening.

It you can actually hear compressor surge (chatter), that in itself demonstrates that your mod is effectively acting like a dumpvalve delete. It might be allowing some air through the holes but if you can hear it reversing, then by definition the holes aren't big enough to allow all the air out and some of it is going backwards through the turbo - which is the thing you said was bad at the top of your post.

The negative effects may not affect the engine as quickly as they might if the DV port was fully blocked but it's a mistake on your part to think that this mod somehow avoids the problems inherent in a full DV delete while still making the turbo surge. You seem to be saying that this mod allows you to have your cake and eat it. Unfortunately, it doesn't.

How reversible is any engine damage that results?