3" Exhaust Butterfly Valve

donpulsar

South Yorkshire Regional Rep
Any idea where I can source one of these ? (I've tried eBay, Google, Yahoo etc with not as lot of luck )





It fits between two exhaust flanges and is cable controlled to allow adjustment of sound levels from within the car.

I've found one at "Apex Performance" but £125 + P&P seems a tad steep to me!

Any suggestions, ideas and help appreciated! :thumbsup:

Cheers,

donpulsar :-D
 

Fazz

New Member
Greenline also do them.

To be honest I'm not convinced they work thou..

was about to buy one, but went to mates pit and put in a similar metal piece after CAT so to block air flow.
So exact same as how this works, and zero difference to noise...

May just be my set up thou... We did find out all my noise actually generates at the very back when the exhaust opens to a 5" tail!!!

So sorting that instead and tail pipe being reduced!
 

campbellju

Moderators
Staff member
I've been looking at a custom exhaust recently. Problem is how to keep some back pressure at low revs to improve Torque whilst not killing the top end. Was originally thinking of keeping my twin exit 2.5" back box. Today I was thinking of just going 3" straight through with one of these controlled by boost in the middle. Just an idea at the moment but thanks for finding what I've been thinking about.

Will definately go for just a full 3" system now as even if I don't go for this, its easier to play around with bits of metal like yourself Ian to see what affect if any it makes.

Decision made, thanks gents :thumbsup:
 

mattygti-r

New Member
they are called an apexi EVC and £125 is about the right price,

they dont make one which will fit straight on to the pulsar

seen a GTI-R with one, they do work, and make a noisy exhuast basically silent.
 

Fazz

New Member
MAtty - I suspect the noise from that GTI-R was generated near the CAT then... and had a small tail pipe/backbox

As it made no difference whatsoever to mine - but as stated mine generates most of noise from stupidly big tail pipe.

Personally, I've seen the Apexi Active Tail silencer in action asn seems quite good. I do like the idea of the exahsut flange but it didn't work for me.

@ Jimmy - in relaiton to the atp product - this is actually a different kettel of fish. it is more a piece of exhasut that you have to weld into your exhaust. Then there is a valve or exit to the side if you like, that opens depending on rpessure etc.

So it effectively eliminates any of the remaining exhaust when opened.
The design in fact is made for a standard exhaust unit where off boost will be stock levels, but on boost the valve opens and the exhaust effectively is shortened to wherever it is fitted - be it before CAT or wherever.

Nice design, but wouldn't reduce noise from a 3" system in my opinion... Especially if the noise is generated near teh back fo the car.

Personally, through my own piece of trial and error I am cutting off my 5" tail, and welding on a 3 or 4". If noise still permits I will probably fit an Active Tail Silenceer which is just a bung into end of exhaust that reduces output at the tail and reacts to pressure also. - can't fit active tail silencer as they come in 90mm and 115mm... much less than 5"...

Reports of Active Tail Silencer bringing a 108db car down to 95db and thus legal for track...
 

Fazz

New Member
Sure Jim.

Results as stated - not confirmed on mine yet but will do as soon as fitted - gonna be couple weeks gotta get tail pipe to suit and find a free sat to go and buy the thing...

Prices very reasonable - $135 so worht a shot in my opinion.
http://www.autocarparts.com/part/list/1591/

Dyno's have proven no power loss - its in the tail anyway. so minimal.

If your exhaust is like mine - have a mongoose and will have the 3" elbow and downpipe then it may suit.
Has brough an S2k down the quoted figures of over 10db.

The flange idea didn't work for me so this is next on the agenda and nice to have positive reports about it.

shop here has it in stock as I say - trouble is my tail is too big at mo so can't test it.

It bolts in to original exhaust and the tail works via a pressure valve. So when little pressure its almost closed and releasing only the minimal of gases etc.

Only bad side is appearance. This is effectively a bung in the tail pipe and so this will be the picture:
 
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campbellju

Moderators
Staff member
Looks like a neat solution Ian. Doesn't look that difficult to fabricate. Can'y your mate help you build one?
 

Fazz

New Member
prob could but for the sake of €100 I'm just gonna buy one and get the reduced tail pipe to match and welded on.

Mate is plenty busy with custom intercooler pipes, turbo reducer pipe and now turbo elbow and downpipe! Think thats enough for now! :)
 

mattygti-r

New Member
oh ive one of those active tail silencers, was custom made by MINES in japan for my GT-R,

the apexi valve made a huge difference, dont know where it was placed on the exhuast system, it had a TRUST exhuast and a massive tailpipe

was at a bluewater meet maybe 3 years ago now
 
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