CBR786

I am planning to run a exhaust mod for louder exhaust note but was considering adding a pair of these vacuum valves you can buy from ebay item number 291094283202

has any body gone this route and do you think I will have enough clearance to install these between the inlet and outlet of the mufflers ? on a 993 C2S

I do not want to live with constant loud exhaust note! hence the vacuum valve route. I did a fabspeed muffler bypass on a pair 0f 996 rear mufflers the sound was too loud and even at idle it sounded like a big block V8 lol

lopro

997 exhaust valve. sounds like an interesting project.

chaoscreature

Did you want to make a remote disconnect muffler bypass?
Most people that use these install them right after the headers or cats for maximum attention grabbing effect.

There is not a lot of room between the inlet and outlet ends of the mufflers but I think it could be done. If they make a 2.25" or 2" version of these it would make things easier, OEM tubing is about 2 1/8" ish so you would need to neck up/down in a very short distance with the item you selected.

NP993

So you change the loudness of the exhaust by pressing a button on a key fob? Imagine explaining that to your date...

(Or maybe I'm misunderstanding how this works?)

Shahrams

I did that a couple of times. There is enough room to add the valve.
The Valve is welded in the middle of the muffler bypass and is openning or closing with a remote (any central locking remote works fine).
You will need also a powerd vacuume valve and a vacuume source from the intake.
But make sure you get good exhaust valves like Pierburg or Brose which are also used in 996-991.
The valves from Ebay are not standing high temperturs and tend to jam.

bcameron59

I did the LPMM with 2" bypass pipes and was looking at putting these valves in the bypass pipes in case it was too loud - ebay item 291120791633

Turns out my wife seems to like the new sound. Even the neighbours don't seem to mind it, though I suspect a few of them may be just a tad envious.

So guess this project can wait a while..

CBR786

YES I plan to do the LPMM with a 2" bypass pipe with this valve contraption inserted welded in between so I can press a button on the dash or remote what ever to increase exhaust noise as and when I require lol. (PSE)

I know a lot of people will mention just do the bypass and live with the increased sound but I feel it might be too loud to live with every day. Is any one in the UK that has done a exhaust bypass that I can possibly hear a live sound bite in person. Utube vids just do not cut it with my lap top speakers I am not sure how loud they are as it is hard to engage unless you are there in person lol.

bcameron59

You could always try the LPMM and then retrofit the valves if you find it too loud.

I found the sound is lovely and menacing at startup & idle, then becomes quite tame at cruising speed, and only growls thereafter when the accelerator is stomped on, or decelerating under load. Perhaps you will find the same; if not, the mufflers are quite easy to access to perform the valve mod at a later time.

Since it doesn't look spousal and public outcry will force me to do the valve mod, maybe I'll do something that's REALLY useful eg dissuading tailgaters from following too closely

Ebay item # 251554736977 (and many more to choose from)