New Mid-Pipe Exhaust

December 2005

I've never liked my Murano's exhaust, it's both too quiet and hangs way too low causing an eyesore every time I see it from across a parking lot.  It seriously bugs me, especially when I go off-roading with that thing hanging down...

In stock trim the whine from the CVT isn't bad at all.  In my mind it's a lot like a supercharger whine, so the connotations it creates in my head are all positive thoughts.  But there are no other sounds to go with it, no exhaust rumble, no intake rasp, no other voices in the symphony of the Mo driving experience to make a proper piece of music...

First step was the JWT Cold Air Intake.  Not only did it free up 6.5HP at the wheels, but it frees up a lovely throaty rasp, almost making one think V8 instead of VQ35.

The next step then is the exhaust.  I'm deciding for now to keep the rear muffler & tips, but ditch the entire center section from the flange behind the catalytic converter, including that god forsaken saggy mid-muffler, to the flange right off the rear muffler.  This allows me to bolt the new mid-pipe right up, and swap it back and forth with the old system at my leisure.  The cheapie way to do this job is to simply cut the stock system and replace only the mid-muffler with some straight pipe, but then you're giving up some ground clearance, possibly some performance, and destroying your stock parts in case you want to go back.

My good friend Michael Smith from MWS Motorsports volunteered to do the deed, and decided on 2.125" OD 16 gage tubing to match the stock pipe, purchasing eight 45 degree mandrel bent pieces which gave us enough bends and straight pipe combined to do the job.

Mo sans mid-pipe:


Stock mid-pipe on the ground:


Note, the left pic below is of the Cat side of the mid-pipe, and the tubing is clearly flared out to a 2.5" flange.
The right pic is at the rear of the mid-pipe where it connects to the rear muffler, and that's a 2" flange.


Next comes lots of chopping and measuring and eye-balling and welding...



And a few hours later Wa La!!!


Where's Waldo the Mid-Pipe?  Look closely to find it...


Peeking above the front passenger side lift support, you can see how hidden this system is. 
And yes, as you can see Michael's l33t W3lderz Ski11lz comes from demonic possession.


More detail back to front:


The two mid-pipes side by side:


Who stole the mid-muffler???  ;-)


This shot is taken literally like 10 inches off the ground, and you can juuust see the exhaust.

Now then, the sound, is BAAAAARELY more than stock.  I used a DB meter on the freeway at 70MPH in D, S, and L, and there was NO change from stock, 89db.  There is a faint low freq growl during acceleration, but that's it, just enough to give you that warm fuzzy feeling when stomping on the gas.  You can hear the system a bit more if you blip the throttle in a parking garage or under and over pass with the windows down, a vaguely 350Z sounding note and bark, but if you aren't trying to do it you really can't tell the difference. 

Here's some high quality sound clips, first you'll hear some throttle blipping and then a 0-60 run:  Stock Mid-pipe and then new Mandrel bent Mid-pipe.

And last but not least, performance....using my trusty G-Tech Pro Competition, I cut my 0-60 by over .2 seconds, now in the 6.x second range!

Peak HP barely increased, but torque got a nice 3 ft-lb bump, and the overall torque curve looks VERY healthy.


In due course if I get bored I'll swap on a 350Z or G35 Coupe rear muffler to get more voice out of the exhaust, but for now this is working great.

-c