Am toying with the idea of a quiet exhaust!
 

Yes that did say quiet! LOL.
Now then, what quiet exhausts are there around that will give me the same throughput of airflow as my Ninja does?
Before that i had a Subaru Scorpion 4" round exhaust which my car was then remapped on.
I dont want to lose any performance, but could do with some quieter cruising! LOL. fcuk i must be getting old ffs. :D

Im pretty bored with my "boomer" too i follow this thread with intrest. I guess im hooked on scoobs but im getting old now!
I no longer have the stereo turned up so far i can hear the engine...LOL

I was also in the same boat,after having the Nur spec R on my STi for nearly 18 months it just got too loud for me.I swapped it for a revolution system still 3" and pipework had very few bends in it creating a better flow IMO and best of all its lovely and quiet (stealthy) and ideal for trackdays/motorway cruising

Another vote for Revolution, IME its the quietest single box full decat there is.

But lets not kid ourselves as soon as the catted downpipe comes off any stystem gets noisy!

Another way to get rid of the 'boomyness' is to go for equal length headers which will quieten things down believe it or not, but you lose the burble. Tubular unequal length headers are less 'unequal' than OE so you can still have the burble and noise will decrease a bit.

Had a full decat Revolution system on my old STi, very nice and not intrusive whilst retaining that flat four beat:D
http://www.revolution.eu.com/

Answer to this query would ideally need use of a rolling road at a quiet time and someone prepared to swap over a few back boxes on the same day to find out objectively the relationship between power and noise.
I'm also getting old and running a slightly modded UK "classic", fully de-catted but with an original type "pea-shooter".
Not yet tried it on a rolling road though with this combination but my own estimate would be about 260bhp but quiet with it.
It should be possible to have the power together with low noise---you don't hear many noisy 911's, Jag's, AMG Merc's do you?--and its my opinion that noisy exhausts just attract the wrong sort of attention and do nothing for the Impreza image.

i had a straight through 3" stainless to a 5" slash cut exhaust when i bought her (the lad owns a modifing shop (endless performance, goole), and makes his own custom exhausts) had to swap it back to the prodrive one for the MOT, my missus is a lot happier now, its not quite the same, but you can have a conversation when the fingernails come out of the dashboard! :lol1:

I have a full 2.5" decat with a magnex centre resonator and prodrive sport backbox. At a recent event my exhaust registered 92dB @ 4500rpm, this is pretty quiet by all accounts unless you still have the OE exhaust with catalytics

Full decat and the original back box works quite well. It's not restrictive unless your running huge amounts of BHP...might even gain one or two horses off-boost :)

I have a standard setup with a WR Sport backbox. You can hear the trademark burble from the outside but in the car there is very very little sound. It's only really audible when the windows are open. I am hoping to get a Prodrive sportcat in there and decat the centre and I hope it doesn't make much difference - I definitely don't want intrusion in the cabin especially since we have a baby on the way!

I have a TSL group-N downpipe, with a matching centre and H&S backbox and that's pretty quite.

I have a prodrive exhaust and also wondered about a very very quite backbox. One that does not loose any poke of course.
Did some looking around and howard and scott will make you an exhaust to whatever spec you want, inc very quite.

dipster

What about the Apexi exhaust control valve, that way you will have the best of both worlds

http://www.apexperformance.co.uk/catalog/product_info.php?products_id=1001&PHPSESSID=2d8e41 ad5d57814

I haven't used it myself but I am definitely considering it, has anybody else used one?

I went from full hks hiper to full magnex and although i miss the hiper, the constant drone wasn't really suitable for daily driving. The magnex gives a nice deep burble without the in cabin drone. Worth a look.

Dave

I went for a sports cat, and that didn't really affect the overal volume, just made the turbo a bit more audible, which I like! :thumb:

Ns04

Funny this thread should turn up.

I'm looking at changing my Ninja backbox for something a little quieter
and less in your face.

I'm finding the Ninja too loud on the motorway and the fact that I have
just bought a decat downpipe to fit will only make it louder.

Rob

If you're intending racing/ track eventing your car a quieter exhaust is a must these days

I had a custom powerflow exhaust made a couple of years ago. Its full stainless and most of the bends were illiminated. The motorway is fine the thing is about 50MPH it gets ressonant inside the car. Since the whole system is one welded piece (no joins or clamps) im interested in someone that could cut the pipe and fit a quieter back box.

Id recommend a Scoobysport back box. I swapped my 4 1/2" jap style box for scoobysport, now the only thing that annoys me on motorway is the roadnoise.

Have a think about mongoose i have one on my 99 uk turbo real nice sound:cool:

Quiet exhaust?

I had exactly the same worry prior to my full decat, thinking it's loud enough, however I was pleasantly surprised that it didn't seem any louder..!:thumb:

Hi I have a trust/greddy power extreme 2 on my classic and i get the power without the booming quite rare to find on scoobys though Id recommend 100%.

Revolution! [/B][/B]Without a doubt! I have been running a decat with a Ninja for some time now and it was getting me down on longer runs. Andy Forrest suggested the Revolution system. My MY00 UK Classic with the decat, VF23 Turbo and Andy F. remap has 315bhp and 298lbft torque at TegSport rolling road recently, so there is no probs with lack of power!!! The exhaust is not silent, but you can have an audible conversation at speed without having to shout!(Unlike the Ninja!)
Buy the Revolution mate, you won't regret it, although I have to admit it doesn't look as good as the Ninja!!

I have got one of these
http://forums.nasioc.com/forums/showthread.php?t=692842

you can link it with a map sensor so it opens on boost but it is quiet enough on loud, not boom`y at all , and flows resonably well @ around 400 bhp,
Have a good one
Tim

edited to add, non catted downpipe on mine