Performance gains aside, I would like to get your opinions on the most quiet aftermarket exhaust systems.
I've heard the Borlas are pretty quiet. Any other suggestions? Also, how is the quality of the fit?

 

I have the TTE Quads, I only notice the sound if I have the window open. or if I am out of the car. the fit is perfect if you get the proper parts installed with it.

 

If you want quiet but a different look, your best bet is to put different tips on the stock mufflers. ANY aftermarket exhaust is going to be SIGNIFICANTLY louder than stock.

But if you're intent on getting an aftermarket one, I'd say the RMM is the quietest.

 

Borlas are still significantly louder... like Bit said, just get the tips.

Another alternative (for Borlas and other brands too I think) is to get an inline baffle (I think there is another term for the part which isn't springing to mind... resonator?) that they offer which is supposed to significantly quiet it down. I've never heard one with them in, though. Borla makes one for theirs, but you have to call them and ask for it.

 

I had Borla on my GS4 before and listened to RMM on another GS4. If memory serves me right, RMM was just a little bit quieter than Borla SS. Mind you, we didn't have any engine modification back then so the noise was generally from the exhaust. It was a fair, but not fully accurate test (my ears can't tell the exact dB). L-tuned is also quiet IMO. But if noise is your major concern, just change the tips like many people do here.

Cheer.

 

Greddy EVO are quite. I only hear when I get on the gas. The Bolt on was easy.

 

Fujitsubo Legalis R. Super quiet. Very nice quality as well.

 

I'm just curious, isn't the EVO the same thing as old greddy PE except they made the exhaust so it doesn't drag so low to the ground? Did they also tone down the noise compared to the old Greddy PE as well??

 

The EVO is a little more noise factor then sportline but less then Borla or HKS. I know because when I was at the shop some other GS were up there to compare with. As far as PE I never heard one.