looking for the quietest possible exhaust system (aside from stock), I've narrowed it down to:

350z Nismo (of course with G35 extension pipe)
Fujitsubo
Stillen Gen.2
Tanabe Medallion Touring

Which of these four is the quietest, and is there another alternative that is even quieter? This is going onto a 2005 Coupe. Are there any other options for better flowing exhausts? Like a G37Coupe cat-back or something? I dont want anything that requires any modification however.

 

No clue since I drive a sedan, but I'm glad I'm not the only member here who doesn't like a loud exhaust on my car.

 

You might check into the Motordyne VQ exhaust.

 

^ there isnt' really any way to "check" into these exhausts. I've watched youtube clips of them all, but they all have different mid-pipes, y-pipes, etc.. as well as camera positioning, throttle under load, etc.. its almost impossible to determine with youtube video etc. I was hoping that some true G35 enthusiast who has attended car-meets would know.

 

The quietest is by far the 350z nismo, which I think you mean midpipe? This exhaust does not offer you any performance gains however gives you that nice tone that you are probably looking for.
The other ones aren't as quiet, I have the Stillen Gen2, and love it. I felt the gains on this exhaust and you can always find a used one in the marketplace for a great price. I am not a fan of the other exhausts only because of the single tip muffler.

 

I highly recommend the Fujitsubo if you're looking for a quiet exhaust. Quiet, 3", single exhaust. Looks great. Sounds great.

The Nismo is a nice choice, too, but keep in mind that not only will you need the extension pipe but you will need to extend the tips a couple inches, too. That involves cutting the tips off and welding some extension pipes.

You won't regret the Fujitsubo, especially with the y-pipe.

Where are you located? Try to hit up a local meet and hear some exhausts there.

 

^ annecdotally, it's my understanding that fuji makes the exhaust for nismo. In fact, I think i remember seeing a thread about it.

 

^^^Haha, yah. I think I was the one who said something about that after Brian@MyNismo confirmed this for me back in 2006.

 

so in order of quietness I'm looking at

Nismo < Fuji < Stillen Gen.2 < Tanabe Medalion Touring < Motordyne VQ

I was thinking about just buying a used Nismo off the forum that has already been modified to fit.

 

Doesn't look like you are considering the hp gains, just sound. Just eliminating or replacing the resonator would probably do what you want. For alot cheaper

 

In doing so, he would introduce rasp.

 

^ i'm mostly just looking to give myself a project to do in my spare time. I just want to tinker with something without ruining the sound of the car. I highly doubt the muffler itself is going to make much difference in hp.. that's going to come from the y-pipe, hfc's, and headers anyway.

for fun i want to do a full exhaust including headers, but I want every single component to be as quiet as possible. I did this on my IS300 and the outcome was amazing.

 

Changing your headers and cats is surely going to make your exhaust louder, even if you go with Nismo, Fuji, or even OEM.

 

i dont want rasp, so my current plan is:

Intake: 06+ HR Airbox (nice and quiet)
Plenum Spacer: 5/16 Motordyne (does anyone make a 1/4" spacer?)
TB Spacer: OBX? (or is there a more reliable brand?)
Headers: Megan? (who makes the quietest headers? preferably with the thickest metal? They cant be long runner because I still want cats)
HFC: Fast Intentions 400 Cell ? (does anyone make anything higher than 400 cell?)
Y-Pipe: 350z 07-08 HR (does this pipe still have cats?)
Exhaust: 350z NISMO w/ Extension Pipe (unless there's something quieter)

 

I assume you are talking about the revup intake box. Not the HR box.

No one makes a 1/4" spacer.