Acoustic Valve... The Truth

[BenR]

pretty much so, in the parts syste it is called an 'air filter silencer'.........sorts that out then, i'd never bothered to look at it on the parts system!

 

[Munson]

So by removing it, we are increasing the induction noise?

 

[ant]

look, i had it - car was quick.

i binned it - car was just as quick + with the viper and c.a.f. plus my soon to be had remap it will be quicker.




bin it.

 

[ant]

oh yeah......................and it sounds sooooooooooooo nice!

 

[nelson182]

So by removing it, we are increasing the induction noise?

I would say so slightly, but the main increase in noise as 7MAT stated would be by fitting a larger custome air feed. (only minimal increase in sound I can vouch for on mine)

As also stated the word acoustic, must refer to noise or sound that varies by having this valve. :evil:

 

[Serg]

ok to clear this up we are talking about the lil black box in the middle of the air feed pipe?

 

[BenR]

yup......the plastic tube with a butterfly in it.

 

[Serg]

thats what i thought nice one ben

 

[7MAT]

 

[TrophyDan]

Think ill try this mod this w/e and put my panel filter in at the same time...

1) What size air feed 85mm / 70 mm? -- someone mentioned if it was slightly restricted the air flow would act more like a ram air effect (squeezing the end of a water hose to increase pressure).
If you have a larger air feed (85mm) you get more of a waft of air
Which is better, what is the compromise size?

2) Do I connect the air feed directly to the air box or do i leave a sort of XXmm ish gap between air feed pipe to air box hole.

I am looking for noise increase



Cheers for any help.

 

[BenR]

You will not get any 'ram' air effect from any setup.

 

[rory182]

You'd think renault called it the 'acoustic' valve for a reason. They didn't call it the 'cold start valve' or a 'mid range range torque increasing valve'.

It'll just reduce noise. Won't it???

Exactly, said it before and was just about to say it again...

a·cous·tic
adj. also a·cous·ti·cal (-st

-k

l)

1. Of or relating to sound, the sense of hearing, or the science of sound.
2. 1. Designed to carry sound or to aid in hearing.
   2. Designed to absorb or control sound: acoustic tile.

 

[TrophyDan]

You will not get any 'ram' air effect from any setup.

Ok, big 85mm feed it is then.

Direct connection or not then?

cheers

 

[BenR]

direct if you can.

 

[BenR]

Exactly, said it before and was just about to say it again...

a·cous·tic
adj. also a·cous·ti·cal (-st

-k

l)

1. Of or relating to sound, the sense of hearing, or the science of sound.
2. 1. Designed to carry sound or to aid in hearing.
   2. Designed to absorb or control sound: acoustic tile.

On the same note, renault hardly ever name anything logically lol.

But i've never heard it called the acoustic valve officially.

 

[rory182]

renault hardly ever name anything logically.

'air filter silencer' in that case it must be for improving low down torque then? lol

 

[BenR]

no, just saying that i've never read it as a 'acoustic valve'.....because as a french translation i could see where people would relate that to tuning pulses.

 

[powello9]

The plot thickens...

 

[Lagerlout]

Yup... accoustic means a bit more than noise or volume.

Remember that crazy french guy made a custom feed to move the 'acoustic valve' (his words) into a better position behind the head light? Crazy!

He reckoned he saw 10bhp after a remap with that setup too. lol.

 

[BenR]

yes, oliver.

He has since made another updated design.

 

[Lagerlout]

Can't fault his dedication! And fair play to him for having a go. Was a bit heath robinson his first go iirc. Is it worth it?

 

[BenR]

far from, he had sorted out the best routing and lengths and method to re-use the valve.

It was quite good and worked well.

And contruction method was pretty good for a home setup, where he made a foam mould then used a gelcoat thick fibreglass and later carbon.

 

[Lagerlout]

I remember. In fact heath robinson is a bit harsh. It's better than I could do in my garage. lol.

 

[nelson182]

Ok, big 85mm feed it is then.

Direct connection or not then?

cheers

If you leave it disconnected more noise/sucking roaring sound will be heard, where as if connected, it is like it is trying to suck air through a straw (restrictive in my opinion but at higher risk of also drawing in warmer air):approve: Up to you. Just experiment!!

 

[mat-nos]

^^^was just going to say experiment yourself, or try doing a test on a rr day and post up your results??!!

 

[clidge]

guys how do you actually remove the valve as my gen 2 kit is coming today and i thought i would remove it at the same time cheers many thanks ps sorry for asking i have no mechanical knowledge what so ever lol

 

[7MAT]

guys how do you actually remove the valve as my gen 2 kit is coming today and i thought i would remove it at the same time cheers many thanks ps sorry for asking i have no mechanical knowledge what so ever lol

1) Jack up car

2) Remove front passenger wheel

3) Remove inner arch liner to gain access

4) Un-bolt and remove, remember to block the end of the small rubber pipe.

More pics here; http://s23.photobucket.com/albums/b387/7MAT/TROPHY/CAI/

 

[rich[182]]

^ 3) Remove inner arch liner to gain access

How's this done without damaging the liner ?

 

[nelson182]

^ 3) Remove inner arch liner to gain access

How's this done without damaging the liner ?

Arch liner is held on by a few plastic plugs which cost about 10p each to replace if you do chew then up whilst pulling them :approve:
7MAt above helped me with my acoustic valve removal, only took about 30mins!

 

[Neil G]

What Proven benefits are there of removing this valve apart from the usual 'my car feels more responsive, blah, blah blah'?

 

[7MAT]

What Proven benefits are there of removing this valve apart from the usual 'my car feels more responsive, blah, blah blah'?

I don't think any body would be prepared to have multiple rolling roads done just to prove a point with an acoustic valve.

But to me it makes perfect sense to bin it as its restrictive especially as I plan to install some of BenR's inlet manifolds and have a custom Superchips remap to get the most of out of my set-up which also includes a Janspeed exhaust system with de-cat.

 

[Neil G]

Why is it restrictive though?.....the airbox has two feeds doesn't it?

Just would be good to have some definatice proof that removig this actually improves the running of the car.

Think I'm going to leave mine in situ for the time being.

 

[George k]

Ben's point that it can not help torque is absolutely fundamental as it is on the wrong side of the air filter to create any useful resonant pulses to improve cylinder filling - the air filter will act as a damper. The only thing that has not been checked out is when it works - in addition to the vacuum pipe there is a solenoid with an electric feed. If anyone has the time, they could put an warning light type bulb or meter into the circuit to see when and if it is activated.

My best guess is that it is to do with drive by noise, particularly for Switzerland

 

[clidge]

chers 7mat however mate i am still absolutely crap with cars any chance of a more detailed how to guide with pics at each stage and tools required cheers many thanks again

 

[MRBILLYUK]

Has anybody asked the dealers what the valve actually does , or better still contact the factory in Dieppe and ask them ?

 

[Fred@BTM]

Has anybody asked the dealers what the valve actually does , or better still contact the factory in Dieppe and ask them ?

answer - 95% of dealers don't know what oil to put in

dieppe, i'll ring my mate

 

[haitch]

clidge, if you plan to run a proper caf by removing the foglight you have to take the acoustic out, as it is in the way. if you are not doing this then leave it alone imo

 

[MRBILLYUK]

answer - 95% of dealers don't know what oil to put in

dieppe, i'll ring my mate

At last we might get an answer once and for all . Does your mate work for renaultsport ?

 

[clidge]

haitch thanks for that mate i am getting my gen 2 kit fitted tonight and will eventually put a bigger feed in so shall i remove it?

 

[Neil G]

haitch thanks for that mate i am getting my gen 2 kit fitted tonight and will eventually put a bigger feed in so shall i remove it?

You have to remove it to get the feed down through the gap and to the fog.