Subaru Impreza WRX STI Forums: - View Single Post - Exhaust Quiet -- stock like sound level -- turbo back exhaust
View Single Post
Old 11-06-17, 05:56 PM  
Becoming A Master Contributor
Car: '18 Camaro SS 1LE
Fav Mod: Don't Need Any, No Subaru
My Threads
Posts: 637
My Subaru Parts for sale

Join Date: Sep 2016
Location: Colorado
DaveC113 will become famous soon enoughDaveC113 will become famous soon enough
Default Re: Quiet -- stock like sound level -- turbo back exhaust

Originally Posted by jaswrx View Post
If "quiet" cruise is what you want, Corsa is pretty much the only option. But don't get a catless downpipe. There really are not many advantages.

With that said, no turboback is quiet on these cars.

If I had to do it all over again, here is what I would do, and I have no scientific evidence to support my theory, but the Y pipe messes the sound up and added noise all in the wrong place.

Buy a single exit tame exhaust like the Q300 (comes out the right side), and be done with it.

The Q300 DUAL and SINGLE do not sound the same, and it's b/c of the Y pipe. If you actually look at any other performance car, none of them do the Y crap. They use a single large muffler section with piping coming out on each end-- much like the GR hatches.

To this day, the absolute best muffler (exhaust) I have heard is the APexi WS2. It in incredible sounding, super aggressive and mean, but really quiet, when you want it to be. It's simply the best of both worlds. Nothing even comes close IMO.

The Corsa is a wannabe Apexi, and the tone is actually pretty similar, but Apexi is definitely quieter and sounds way way better on ELH.

I am strongly considering buying the Invidia 300, chopping the muffler off, and buying the Apexi WS2 muffler. It's that good sounding, all while being drone free at any rpm.

Listen here, but of course, the video does not do justice.
Apexi Noir 2005 Saab 9-2x Aero - YouTube
Subaru wrx apexi exhaust - YouTube

I like the sound catted and with a resonator. It can get way too raspy if you go catless and no resonator, and really noticed once you go ELH.

I tried to clarify my previous statement about the split in the exhaust, it does mess with the sound and it's done on purpose:

Originally Posted by DaveC113 View Post

The problem is the way the T is designed and with the SPT it's intentionally meant to drone and be loud at lower rpm and not be too loud at WOT. The T in the SPT is a 90 degree angle which will reinforce sound with the same wavelength or fractional multiples of the wavelength.

edit: that should read: sound with the same wavelength as length of the exhaust tubing from the cat to the T. The sound at these frequencies is reinforced via constructive interference and you get a bassy drone. This is 100% intentional and imo ridiculous.

The T on the stock exhaust is not a 90 degree angle and it doesn't drone to the same degree vs the SPT. edit: Any discontinuity will reflect sound so the Y will always effect the sound and will always make it bassier, so the shape of the split has a major effect.
DaveC113 is offline  
Likes 0 Dislikes 0
Reply With Quote