So I cut open the spare OEM stock muffler I have for my 2011 G37 Coupe.

Just doing this for curiosity... No need to tell me this is mostly a waste of time. I am fully aware

The ends of the two J-shape parts look open but they are completely blocked off. So all the exhaust is forced through the perforations.

I think just removing the J's would let through more flow and sound, while still keeping the drone-cancellation properties for highway cruising.

The little pipe on the left side outlet looks like it is there to suck condensation/water buildup out of the bottom of the muffler can.

The left and right dividers are solid, there are no passages through them, except for the small diameter pipe that connects the left and right chambers.

The end chambers have the outlets passing through them, with perforations in the pipe. They also have two small openings that line up with that small diameter pipe.

If I end up modifying the internals and welding it shut and happen to like the results, great. Otherwise, don't care, really just wanted to see what's inside.

 

Ha that's crazy looking. Thanks for sharing

 

Definitely not a waste of time, thanks for taking your time to do this, always wondered what it looked like inside!

 

Interesting...

 

good job! is this from a coupe/sedan? sport? (I think sport/non-sport may have the same muffler, but not sure)

 

It's from a coupe, and sport and non-sport have the same muffler.

 

Are you planning on doing any modification to it?

 

this is interesting. thanks for take the time to share this

 

I cut open the J-shape parts as best as I could, and welded the can shut.

This allows more free flow between the IN and OUT.

Sounds great! My G37 now sounds a lot like my stock 04 G35 coupe did, except that it is not intrusive or loud at low rpm and when idling, like the G35 was.

to me, in stock form the G37 is way too quiet if you are used to the G35.

So there is no drone. Nice sound when you lean on the gas, and mostly quiet when you are not. No video clips yet - maybe I'll get something in the next few days.

If I was going to open it up again, I would cut out the "J"'s completely so there is even more direct flow to make it a bit louder still.

So, you can get a 370Z muffler in a scrap yard for, say, $100, play with it, pay your local welding guy $50 to close it up for you. Food for thought. It is not raspy, it's not chrome. I'm very happy with the results.

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mikeb2004, are the pics still around?

 

Oops, they were moved some time ago... I just fixed the links. Enjoy!

 

thanks man.

 

hard to tell from picture but is the j-shape connected to the inlet or is that plate (circled) a divider between inlet & j-shape?

 

I want to revisit this project a little.. I didn't have the sense to check if there were spring loaded flaps inside the big holes on the sides. They do that on Maximas (or at least they used to - I don't know if they do on the current generation).

Has anyone else cut open the muffler who can check, so I don't have to bust it open again?

 

It's connected direct to the inlet. The plate is a strengthening part where the pipe enters the muffler, i assume since the muffler is so heavy.

At the end of each J, it is capped off by the way.