For quiet and cheap put back the stock or nismo axle back muffler.

Arguing opinions of sound levels online is always going to seem a little silly... but I am firmly in belief you just cannot have 3" system and an SC without a radical redesign if you want tolerable noise levels. Turbos affect that noise level a lot, not just somewhat.

Had a guy come by last night with Berk HFCs and Powerhouse Amuse1 CBE and he flipped out when I turned mine on and heard.... he thought his was pretty loud.

Are you kidding? Why not just give up and go back to NA then...

That is NOT a solution. -_-

Sorry for reading the OP's question.

Yeah, because basically choking the f*ck out of his boosted car is a legtimate solution...? :facepalm:

My experience.....

When my car was NA I installed the Fast Intentions CBE and the sound was great. Then I installed a Stillen SC kit and the sound got much louder. Next was a tune by Seb and again the sound changed, this time to a much lower and throaty sound.

Every change you do will affect the sound and level. I absolutely love the sound of my Z now!

Stock cats or test pipes?

And your solution of no solution is better. And just to educate you the muffler itself provides only a minor amount of restriction. I don't even think any list any gains from the axle back for the Z. It's the cats and small 2.25" dia piping from the exhaust headers down that significantly restrict flow. I doubt the loss would be greater than 1% which is not noticeable and you get a "quiet" car which is what was being asked.

I would think it sounds awesome too. I'm NA and recently was tuned. I was surprised at the difference in the exhaust sound. And I have stock cats.

How is the stock GTR exhaust so quiet? Seems you should be able to simulate that setup on a 370Z as well.

After reading through the comments again there are not a lot of options that will look pleasing to the eye trying to cut down the noise coming out the exhaust do to the restrictions that start out of the manifold. When you add a supercharger or a twin turbo you are pushing a lot more air through the system and the restrictions will cause an increase in sound and can cause performance issues due scavenging. A 3" down pipe is needed to benefit a 3" exhaust system. This will significantly cut down on the sound. The Motordyne exhaust only becomes 3" where it meets up with the connection to the y pipe so the sound is actually magnified. I have had the pleasure of riding in a Z that had a twin SC and a Motordyne exhaust system on it. Yeah she was loud and sexy as hell. I doubt there going to any other exhaust will change anything significant because of the amount of air moving through the system. Yes, I think maybe a system like Armytrix might help to a degree but that is an expensive option that may be a fail. I would suggest having a baffle or butterfly value put in that can be manually turned on or off.

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What about the garageline exhaust? It's looks like a higher flowing version of the OEM exhaust. Unfortunately I don't think a ton of people on here have it... It is very cost effective too!

Also, I think it would be a good idea for the OP to give Sebastian a call regarding a solution as a 3" down pipe and exhaust could potentially impact performance negatively because a SC doese need some back pressure to make optimum power so it's a catch 22!

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Stock cats for now.

That is why it sounds so good. The best sound I ever heard coming from a Z was when I had the stock cats with FI exhaust. Take those cats off (because boost) and its a total game changer. They act as 2 giant mufflers.

Your cats will eventually blow out on you.

Because it has cats.

Cats that were designed for forced induction.

And turbos. They make an enormous difference.