350z Muffler Disconnection (MUCH LOUDER & MEANER sound)
 

Hello all,

A little while back after reading a thread on here that mentioned disconnecting the muffler to get a louder (obviously) and meaner sound, I decided to go ahead and try it. All I have to say is DAMN! The car sounds wickedly mean and basically like it can rip your ball$ off lol. For any of you out there who don't mind or really like the sound of a loud mean car, I'd say definately give it a shot. I'm not mechanically inclined, but it took my dumb a$$ about 45 minutes to disconnect the muffler and re-mount it so it would be stable and not move when I hit a bump or something. For any of you out there who don't wanna pay $$$ and have a 14mm ds (deep socket) metric along with a 12mm, you should give this a try. I personally didnt' wanna remove the pre-silencer as the sound clip I last heard I thought sounded a lot more along the lines of tin can sound which I personally am not a fan of. But this sounds like... close to a formula 1 car rather than a 350z lol. I can't really describe the sound, and I'll try to find a means to get some good sound clips for you guys who are interested. Simply put... when you punch it, a square mile can hear it >;-).

PROS: For all you nuts out there that are like me and love the sound of a LOUD + MEAN tone, then this is for you! The car is LOUD. The car has a Eurpean muscle sound, and the always welcome American LOUDNESS lol (IE. it kiks a$$).

CONS: It's LOUD. The in-cabin noise is definately raised up a notch and will cross sound waves with whatever you are listening to (which I personally don't mind). Don't get too pedal happy around cops as they can possibly go deaf and give you a ticket distrubance of the peace in the process ;-).

+/- POWER: Now this I'm not sure about and personally don't think I get any more power. However the car seems more squirly and easy to break traction but I attribute this to the placebo effect rather than anything credible. I don't have the money or time to go do a butt dyno unfortunatley :-(. I think sub-consciously since I love the new sound and gas it more without realizing it, THAT causes me to spin the tires noticeably more than usual.

If any of you are interested in trying it out, here's some possible guidance for ya.

What you need:
1.)Rachet
2.)14mm deep socket
3.)12mm deep socket
4.)Flat-head screwdriver

Diagram (ASCII style)

---[1st muffler]---[Target Joint]---[2nd Muffler]2x--[Tips]

Directions:
**Note that these bolts are on pretty damn securely so you may need a second person to "leg press" the rachet to get to loosen the bolt.

You will want to use the 14mm ds (deep socket) to loosen the (3) bolts that are holding the "Target Joint" together. At first I thought there were only two, but there is in fact three. One side has only one bolt, while the other has one bolt securely mounting the ground lead for a sensor, and a second bolt behind that to hold the joint. So it's basically two bolts stacked on each other. After taking those bolts off and letting the ground wire hang freely, there is a rubber bracket which holds the muffler in place on (looking from behind) the top-right portion. It will be connected an aluminum shinnyish plate. You will need a 12mm ds to loosen that bolt there. Once you have removed that bolt you can then simply rotate the rubber support downward.

**(Note that there are two more rubber brackets, bottom-left and bottom-right, the bottom left has 3 bolts attaching it to the support plate, while the bottom right has one). Dont mess with these as these will keep the muffler still secure so it won't move around.

Now after you have removed 3 bolts and one screw, you can detach the target joint. The joint is secured from whomever machine tighted the bolts so you will probably need the flat-head screw driver. I used the flat-head in-between the lip of the target joints brackets to loosen by manuvering the flat-head to wedge them apart. I only used the flat-head along the bottom on the right side, middle, and left side of the brackets. After that it was simply a means of muscleing the pipes apart just enough to get the two screws (which are welded to the bracket) to come out of the holes so I could manuver the 2nd muffler section of the pipe on top of the 1st muffler section pipe. So after this the pipe will basically look like 1/2 is free flowing while the other 1/2 is still somewhat connected to the 2nd muffler pipe. I then went ahead and put the ground wire back onto the screw it was originally connected to (I also tried the left screw but there wasn't enough slack). Then I put a bolt back on the left screw and tighted back on to the point where it made contact with the bracket, but I only tightened it enough to the point it felt firmly in place but not to the point where it could bend the bracket. I did the same thing with the right screw which had the grounding wire back on it. Same thing, just tighten it enough to make it secure but not bend the lip.

After this your pretty much ready to turn the engine and rock & roll ;-). No engine light or anything like that either :-).

A little note about the sound:

1-3k: Very low, mean & strong tone that travels.
3-4k: Seems to be somewhat neutral as in it's not loud but not quite either. I use this rpm range when I'm by a cop :-D.
4-6+: Simply screams, damn loud and damnnnn mean sounding >:-D

In all, for the +/- 45 minutes you may spend laboring on this little "mod", it is a great way to up the ante of your 350z. It makes the car sound so much louder and meaner, very assertive and intimidating sound in my mind :-). After trying this, I'll leave it as is as I absolutely love the sound! I gave a consideration to removing the pre-silencer until I heard a sound clip, and this was a very welcome alternative that costed me nothing but a little sweat and time out of my day. If your interested in trying it, just do it, it can make all the difference ;-).

L8trz,
--Justin

Anyone have any file hosting space?
 

whats up everyone,

welp I went ahead and used my ghetto laptop to grab a recording of the exhaust sounds from in the cabin and outside the car, but the file's are greater than the max allowed upload file size (go figure). In cabin is 600k, and outside is ~900k. Anyone got some hosting space so I can send the files to that person and let every1 have an opportunity to kinda get an idea of the sound?

If you do, feel free to shoot me an email of where to send the files to at "domainwepr@yahoo.com".

L8trz all,
--Justin

Sound clips
 

Okay,

Never mind the 2nd hand hosting post earlier ;-P. I went ahead and signed up with Angelfire and now have enough space to get you guys some sound clips. Now just as a fore-warning, these clips suck as my laptop's mic sucks. The outside clip's speaker cabilities notably hit their limits when I'm revving lol. Anyhow I'm still working on getting a much better quality clip, anywhere, here they are:

http://www.angelfire.com/linux/350z/nissan350zcabin.mp3 - This clip was inside the cabin with windows rolled up

http://www.angelfire.com/linux/350z/...50zoutside.mp3 - This clip was outside the car about 4 feet away?

L8te,
--Justin

Awsome work! But is it too loud? Illegal? I belive VA state law is 95dba, or something..and on a more important note, is it emissions legal? I would think it'd release more gases/ect into the air?

I did this awhle back, but have since re-connected it.


The sound is loud, inside the cabin. The sound outside the cabin, close to the car is impressive, and the sound is awesome at idle. if you simply disconnect the two pipes, your going to have a lot of air still travelling into the muffler, quietign th esound. If you put say a restrictor plate in front of the pipe, you're going to notice a balls-ass loud sound.

You won't get pulled over simply for the sound, unless the police officer is either right next to you when you're on it 100 percent, or he happens to be taking a ride in your car.

Its not emmisions legal obviously, but it takes roughly 2 minutes to tighten the 3 bolts back up and seal the exhaust.

If you do decide to do this, make sure and remove the small ringed metal seal that is inbetween the two pipes, also make sure and fasten down the small sensor in between the two bolts. I have pictures at home for anyone wanting more info. Its a good change for a few weeks, and a quick mod for the track.

-Z

Not to put down your work and all, but I personally hate loud cars. Have you asked your neighbors what they think? Noise pollution is one of the worst, and I don't really think it's considerate to those around you.

I like the sound the 350z makes as is (with muffler). My Toyota Corrola can make a nasty loud sound too if I take the muffler off (or more likely when it falls off - happened twice to me).

just my thoughts and opinions.

To each his own, but I had friends drive the car at various speeds while I listened at various places and i really didn't think the noise was obtrusive at all. Sure it was louder than the car came stock, but such is the point of breaking the line to the muffler.

that sounds great... if i rolled up next to you @ a light and your Z sounded like that, I probably wouldn't try to race you....probably not...
But that is definately a really unique sound. I like that..: LOUD IS GOOD you think any of my rides have been close to quiet?

Damn, that's tight, I would love for my Z to sound like that. But, I gotta keep the mufflers on, too many cops around here.

Actually , yes it would be emissions legal. You are just taking off the muffler which does not clean up the exhaust at all. In fact it "muffles" it just like the name implies.
Besides, if you take off the muffler you still have the silencer and then 3 (count them) yes three catalytic converters!

To you BShockley thats plenty to keep the car quiet enough so we dont wake you.

Hell, cars are starting to come from the factory with no muffler! Dodge Neon SRT-4 to name one. No BS. I just raced one today. IT didnt sound to loud.

I shelled out for the Borla myself, but for those of you on a budget, there would be nothing illegal about killing the muffler and fabricating a dual exhaust from the muffler flange on back.
The guys at midas will do this for you.

I know there would be nothing illegal about it since cops are concerned with excessive noise and violating emissions regs.
Just dont mess with your cats! If legal issues are the only thing keeping you from 86ing your muffler, dont worry, just do it!

One thing I am unsure of however is gain. I dont know if the engine needs the backpressure or not but my guess is that the cats and silencer supply enuff of that.

your links arent working right now Justin, but I cant wait to hear what it sounds like. thanks for sharing with us.
Geez I hope I didnt waste 700 on an exhaust when I couldve just used a socket wrench!;)

I think you mean 4 cats (2 on each side). :D

Wow! Its really starting to catch on now. I removed my muffler many moons ago because I to like the sound of the car much louder and meaner plus it only took me about 80$ to have portland muffler make a pipe with my stock tip to get the exhaust out the back where the old muffler left off. I also have black/polished Injen CIA and I will say the 350 is getting much closer now to the sound and performance that Im looking for and the car is roughly 30 pounds less. The only thing that sucks is after installing the CIA the idle is low and rough now.

the sound is loud...but is SEXY!!!! :icon04:

err....sorry, i'm not diggin it. It's loud alright but not like refined power. If sounds um... like you cut your muffler off. If I pulled up next to you at a light i'd think, man, that dude needs a muffler. Strange thing to do to a 30K car that already had a great sound..................but like someone said, to each his own.:(

Did you try a grounding kit? maybe...

Sounds sweet to me. Cant tell for sure though until I hear a better sound byte.

Thanks again for the efforts!:D :D :D :D :D

I thought it was 3. Check out the pic. south of the Y there is just a silencer and a muffler. Where is cat 4 hing at?;)

OK, the two real cats you have circled each have a cat in front of them with an O2 sensor between the two. The first one lies more vertical between the headers (exhaust manifold) and the second cat.

The thing circled in the middle is the Nissan factory Y ("Y" description used loosely) pipe with a fancy cover. I have attached pictures of the area with the cover removed.

Yes we have a car that just sits there and gets to be a test mule (for nearly everything) . . .Thanks Doug!


http://mywebpages.comcast.net/adam.b...ssanypipe1.jpg

http://mywebpages.comcast.net/adam.b...ssanypipe2.jpg

my brother has the mustang gt with 6 cats... well none any more he got an off-road h-pipe and he has the loudest car around the surrounding towns :D awesome

This is sort of true in my eyes also, it does give it a more raw sound now without the muffler, but its a good sound. The 1 stock rasonator acts like a muffler just is not enough now if there was another stock resonator welded on giving us 2 it would take a little rawness out probally making it sound (perfect) WARNING just speaking for myself.