guys, subaru club has list with exhaust from loudness to more quiet
it is very convenient
so want to know most loud exhaust for ct9a
who can help?

 

I can help start the list, but there are no promises that it will take off. There was a thread on this already, but it kinda died. To every new poster, copy, edit, paste, and update the list as needed in your new post.

The assumption is that this is strictly a list for cat back exhausts. As you know, a high flow cat, test pipe, or aftermarket downpipe will also increase exhaust dB's. In general, the more exhaust restriction, the more resonators, or larger resonator size there is, the quieter the exhaust.

Quieter

1- OEM Cat Back
2- Greddy SP2
3- Greddy Evo 2
4- Fujitsubo Legalis
5- Fujitsubo RM01A
6- Tanabe Touring Medallion
7-
X- No Exhaust/Front bumper downpipe cutout

Louder

 

Buschur bullet should be #5

 

This list will be entirely subjective unless someone actually goes through the trouble of measuring each exhaust posted. Hell, my exhaust is louder than my exhaust on someone else's car.

 

Agreed, too many factors. Downpipes, mid pipes, test pipes, hfc's, cams, so on and so forth. So many variables.

 

Turbo is a variable too. My car got a lot louder when I put the red on it.

 

Yes, there are too many variables, but I think what the OP is after is the general consensus. We don't need exact dB figures, but more like what we have known to be loud and what has the reputation for being quiet.

For example, we all know for a fact that the Greddy/trust ti-r is louder than a Greddy Evo2 regardless of what test pipe, downpipe, turbo configuration it has.

 

1- OEM Cat Back
2- Greddy SP2
3- Greddy Evo 2
4- Fujitsubo Legalis
5- Fujitsubo RM01A
6- Tanabe Touring Medallion
7-I'll pencil in Tomei here ( I think it sounds perfect and isn't too loud)
X- No Exhaust/Front bumper downpipe cutout

As stated , hard to document catbacks when turbo's, cams and compression are changed over stock.

I'm VERY picky but chose this exhaust based on its sound and lightweight since its Titanium. My car lost almost 50lbs with a DP, TP and catback. It also picked up 50whp on the same tune afterwards. I've driven my car 30K and this system is delivers power,sound and isn't too loud.

Here are few clips that may help .

This video convinced me years back. (sidenote looks like it was filmed in the hot rod /motortrend garage)


My car.

 

Quieter

1- OEM Cat Back
2- Greddy SP2
3- Greddy Evo 2
4- Fujitsubo Legalis
5- Fujitsubo RM01A
6- Tanabe Touring Medallion
(X-1) - Sheepey 3.5" full system, Aluminum with test pipe
X- No Exhaust/Front bumper downpipe cutout

Louder

 

 

You're not asking too much. Here's a video of a built Evo 8 that was running a Tomei Ti and was swapped form a Tanabe Medallion Touring (I have this same exhaust )

 

Unfortunately this type of list is very difficult to make. It all depends on what certain individuals consider loud or quiet and what the can remember it sounded like when they heard it. Not to mention the supporting mods one car has such as Downpipe, exh manifold, turbo, high flow cat , test pipe and also important the brand used for each. Different thickness of exhaust tubing and designs may change the sound slightly .

For what its worth here are all the exhausts I had from personal experience. Please note for my taste, if its 1 db louder than stock its too loud. Just to give you an idea. Also dont be fooled with video clips. They dont capture the exhaust dynamic / loudness of an exhaust unless you can compare to OEM in the same video clip. Otherwise turn the volume down on your PC and that side exit straight through muffler is as loud as OEM.

Scale of 0-10 (0 is OEM TBE and 10 is just o2 housing dumping to atmosphere) From what I remember here is the list:

Buchur Full 3” TBE with 6” center magnaflow muffler in place of the cat and with dynomax VT muffler in the rear. This was the quietest system I had. Sound quality wise it kind of sounded like a tractor though. It had a flapper inside the muffler that would open and close. Normal driving it was closed, WOT or partial boost the exhaust pressure would push it open. WOT it was actually not that loud sounded like a quiet wastegate opening, if that makes sense. Stock like quiet normal diriving but like I said sounded like a quiet tractor. (1 scale)

Buschur 7” Magnaflow muffler rear with 6” magnaflow center quietest of them all as a full straight through turbo back exhaust. Louder than stock still, but for complete 3” straight flow through this was the quietest I had as a straight flow through exhaust without any flapper system that opens and closes. (2 scale)

Cobb- Quieter than the Tenabe as a full TBE but not stock quiet. But gets a little louder over time as maybe internal sound deadening materials burn up ? (3 scale)

Tanabe Touring - Quiet and pretty much perfect as a Catback with oem downipipe and cat. But it gets louder for my taste when completed as a full catlesss turboback. Also its not completely 3” . It tapers inside the muffler. (As TBE 4 Scale , as catback 1 or 2 scale)

Buschur Bullet mid muffler and custom Vibrant Oval muffler rear. As full TBE it was not even close to as quiet as I wanted to get. It was still on the loud side. (5 Scale)

RRE stealth - I dont know why people call this a quiet exhaust. It was not really that quiet at all. It looked oem like because its painted flat/matte black but it was not quiet as TBE. (6 scale)

Jun BL - Loud about a 9 scale. Excellent quality and build but loud TBE .

I think I’m missing a couple things I may have had or done. I did run 3” Works midpipe exhaust piping mated to the oem muffler with 3” downpipe and catless midmuffler. It became a little louder than oem but not too bad. It just had a lot more Bass to it. But inside the car it was kind of perfect. WOT was great as well, nice and quiet.

I also tried another 5 or so downpipes as well, but thats a different story.

Eventually I learned that unless you engineer and invent your own super muffler, nothing else exists thats a straight flow through 3” muffler that will make a catless system exactly OEM quiet. But you can make a system that has a electric or Boost Actuated cutout that mates before a restrictive muffler with only purpose to keep it quiet. Only problem is I want to be quiet when I WOT as well.

 

Quieter

1- OEM Cat Back
2- Greddy SP2
3- Greddy Evo 2
4- Fujitsubo Legalis
5- Fujitsubo RM01A
6- Tanabe Touring Medallion
7- TurboXS RFL Ti
8- Tomei Ti
(X-1) - Sheepey 3.5" full system, Aluminum with test pipe
X- No Exhaust/Front bumper downpipe cutout

Louder

Added the TurboXS RFL Ti. As subjective as this list is, I haven't personally heard anything louder unless it's aluminum, titanium, or non-existent (and depending on the car, it's been louder than some titanium exhausts).

It's called RFL for a reason...

 

I am running the Tanabe Medallion with a downpipe cutout. I think it's just about perfect in my opinion. Sounds great, but quiet enough to not drone or be obnoxious to the neighbors. Open the cutout and it sounds like a raped ape...

 

A lot of people run and love this exhaust, including e_kobz and I. It's very streetable and not restrictive at all. It also doesn't have the cylinder muffler look that police are attracted to. If you shine a flashlight through the exhaust tip, it looks like a true 3" exhaust all the way, but i'm skeptical.

If I remember tonight, i'll take pictures and a precise measurement of the inside of muffler portion since we already know the piping is 3". Unless anyone can find a datasheet and save me the trouble haha. According to their website the pipe Diameter is 80mm and the tip is 100mm. They usually list whenever there is a taper.