I have a full 2.5 inch exhaust on my car, it's loud as hell (car is NA) I come home in the early hours regularly it's annoyingly loud and wakes the whole bloody street up. as well as attracting a lot of the wrong kind of attention. So i have decided to trim it back a little, Put in a butterfly valve after the muffler and a dump pipe above the diff. Then putting on a brand new standard VL muffler and tip. so that when i'm just cruising around it's using the standard vl tip and it's quiet and the cops will leave me alone, or i can hit a switch on the dash, and the butterfly valve will open up the dump pipe. This is a pic of what i need Anybody know where i can get one?? i've already asked a few exhaust shops and no luck yet. Some original photos have not been recovered yet.

You could always put a turbo above the rear axle as an effective sound dampener whilst simultaneously providing boost through long pipe back to inlet manifold which acts like a intercooler. There are a few such remote turbo installations in US, you dont need the heat you just need the gas flow and as turbo exhaust is close to atmos its quite efficient. Wouldnt it only be necessary to put a butterfly after the existing muffler to stiffle the flow enough so the back pressure stifles the separate pressure waves which give that throb already and it would act like a muffler anyway...

lol nah the car is staying NA and if i went turbo it would certainly be located in the engine bay. I'm doing it like this kos I want the car to appear completely stock from the outside, and the valve will just be a convenient way of silencing it when i need to.

If anyone has no idea what he's on about...you can quickly read this http://autospeed.drive.com.au/cms/article.html?&A=2291 Basically the exhaust sound is controlled by something like a intake butterfly, it uses the vaccum line to open/close the butterfly. Plant foot (it opens) Lift foot (closes) Looks like an expensive way to go, there is some contact details on the bottom of that page if you wanna buy one.

mmmm, Yes does seem a bit expensive for what you get. Since a basic muffler is just a restrictor anyway, albeit with a bit of resonance then wouldnt it be worth trying a restrictor just after your existing hi-flow (noisey) muffler. And since the exhaust temp at that point is much lower then you wont need a steel butterfly housing for the purpose of a trial or even for a couple of years of use. ie. Plumb in a largish throttle body after existing muffler or somewhere before the tail pipe so you cant see it from behind. Run a simple bike cable to a hand brake type actuator in the cabin so you can make it fully open to almost closed. This would be a cheap and relatively easy way to try something for a while before making a commitment to anything more sophisticated down the track. I have an XF throttle body you can use for a "few bucks" if you getone of my fuserail kit and that comes with interest in helping you try out the idea Some original photos have not been recovered yet.

Have a chat to a few diesel specialists, they may be able to hook you up with a modified exhaust brake. With a few mods (ie dump pipe) I am sure one would do what you are after.

Quote: Originally Posted by silverRB If anyone has no idea what he's on about...you can quickly read this http://autospeed.drive.com.au/cms/article.html?&A=2291 Basically the exhaust sound is controlled by something like a intake butterfly, it uses the vaccum line to open/close the butterfly. Plant foot (it opens) Lift foot (closes) Looks like an expensive way to go, there is some contact details on the bottom of that page if you wanna buy one. Sounds to me like his is an electronic setup ("switch on the dash"). What you've just described is effectively an exhaust brake is it not?

AUTOBARN falkner in melbourne had 1s that are lever operated, there $350 for a 3' single setup, ive made my own lever operated twin 3' ones on my car and they work unreal

Yeah VLhero has the right idea, I want mine to be set up more like an exhaust switch than an exhaust brake... sort of like a stealth switch. so i can make it quiet when i need to, and leave it open the rest of the time

Forget the terminology about any sort of brake - we are not considering closing off the port altogether. Bear in mind mufflers do muffle sounds partly due to restriction and adding a restriction (butterfly partly closed) will reduce noise, seems worth trying without immediately going to the expense of extra piping from sheer engineering experience of course Some original photos have not been recovered yet.

http://www.quicktimeperformance.com/QTEC/index.php Look at that site mate, its exactly what ur after. Its called an exhaust cut out. Ill be getting one on my setup. It will consist of a 4 inch dump, then 3.5 inch to a fake looking cat that will be a muffler, then a proper 3.5 inch muffler, then 3.5 inch to the back. Id imagine it to be loud as all hell and i dont want to always be driving round like that especially near cops. Im going to run one in the exhaust above the diff so i can control the noise. Should work a treat

Yeah that setup is basically what i need except i don't want it to be controlled only by the throttle. I want the option of driving fast sometimes and it still being quiet (like going to work at 5 AM) . mayb i'll put one of those systems in attached to a dump pipe and have a vacum switch on the dash to adjust it. cheers for the info guys it turns out this is more complicated than i thought Some original photos have not been recovered yet.

I have this setup in my car. Flick a switch and its loud, flick it again and its stock volume. email [email removed] A 2.5inch electric cutout with a on off switch is only $165!! When mines open all that the exhaust runs through is a pair of turbo's and a hotdog mini muffler and dumps just before the diff.. When shut exhaust flows to the rear stock muffler.