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Jan. 29, 2011 7:36 a.m. Twin_Cam SuperDork

Educate me, please.

My sister has purchased an '05 (I think) 2.5RS. She wants it to be louder. I told her I would investigate exhaust systems for it. I'm pretty sure she doesn't care about more horsepower, she's really just looking for sound. No full-length systems, cat-back is good enough. Build quality should be reasonable, price should also be reasonable, but doesn't have to be dirt cheap. Noise level is also another factor...she lives in a neighborhood, with cranky neighbors. If it's too loud, that'll be a problem. I would make a recommendation, but I am clueless about Subarus. Will any systems that fit a WRX also fit the RS? I can't imagine they're much different from the cat back.

In related news, she has relinquished her old car (a '96 Saturn SL2 with completely-rebuilt-by-me engine, with some body damage due to her being a terribly unsafe driver) to me for $1. What's the highest placing S-series in Challenge history? I can't beat it, even the Challenge budget is too big for me at this point.
Jan. 29, 2011 8:31 a.m. chknhwk Reader

Personally I like the home brew exhaust systems. I like mixing and matching - are there any decent exhaust shops near you? Can you look under it and take some measurements for it? I'm thinking some Flowmaster 40 Series and a cherry bomb for a center resonator would sound pretty decent.
Jan. 29, 2011 8:41 a.m. Rob_Mopar HalfDork

chknhwk wrote:

Personally I like the home brew exhaust systems. I like mixing and matching - are there any decent exhaust shops near you? Can you look under it and take some measurements for it? I'm thinking some Flowmaster 40 Series and a cherry bomb for a center resonator would sound pretty decent.

I had an '01 2.5 RS for a little while. Cut the muffler off the end by the tailpipe and stuck on a Flowmaster 40 Delta series. Left the stock resonator in place in the midpipe.

The car had a nice deep tone to it without the usual Flowmaster resonance. Loud enough to know it's not stock, but not loud enough to draw unwanted attention.
Jan. 29, 2011 9:16 a.m. fornetti14 HalfDork

You can have any shop cut the muffler off and weld on just about anything.

I've tried a straight thru Magnaflow (too loud) and ended up with a Flowmaster.
I believe the axel back STI exhaust would work but might not be loud enough if that's what she's looking for.
Jan. 29, 2011 9:21 a.m. ScottyB New Reader

keep in mind that without an aftermarket unequal-length header it will be like any other 4 cylinder engine - no trademark subaru wharrgarbl sound. borla replicas on ebay are a fine choice and have better build quality than the header they were copied from. UEL headers won't do much for power, though (she probably isn't concerned with that anyway)

try an STi axle-back first. it should bolt right on and the hangers match. lots of guys are looking to unload them for cheap as they replace with full aftermarket systems.

if she still wants more volume, any 2.5RS exhaust will "fit" although you may have to tweak the hangers a bit. i cruised various classifieds for a while until i was able to source a header for free and the cat-back for $75 off of an early RS, and fixed both up with a little work. took forever, but it can be done cheaply if you aren't in a hurry.

here's a clip of what my '05 sounds like, system details are noted in the video. http://www.youtube.com/watch?v=KW-8YgAdHLc
Jan. 29, 2011 9:55 a.m. HiTempguy Dork

ScottyB wrote:

keep in mind that without an aftermarket unequal-length header it will be like any other 4 cylinder engine - no trademark subaru wharrgarbl sound.

er, I don't believe that to be true. The factory manifolds are not equal length afaik, therefore, it WILL sound like a Subaru (just not as aggressive).
Jan. 29, 2011 11:43 a.m. 92CelicaHalfTrac SuperDork

HiTempguy wrote:

ScottyB wrote:

keep in mind that without an aftermarket unequal-length header it will be like any other 4 cylinder engine - no trademark subaru wharrgarbl sound.

er, I don't believe that to be true. The factory manifolds are not equal length afaik, therefore, it WILL sound like a Subaru (just not as aggressive).

That's kindof what he said.

Factory is unequal length, and gives them that sound, so if i you put an equal length manifold on there, it'll go away.

The Gobstopper is a good example of this.
Jan. 29, 2011 5:18 p.m. ValuePack Dork

I'm running the factory exhaust back to the rear axle on my Impreza, where the muffler's been replaced with a straight pipe out the back. It frankly sounds amazing, but would be too loud for some.

Hack off the muffler(it's where most of the restriction on the factory exhaust lies), replace with a suitable muffling device. I like the Flowmaster 40 suggestion, a 24" Cherry Bomb would be ok, etc etc etc. Melon launcher/N1-style cans sound perfectly awful on N/A cars.
Jan. 29, 2011 7:02 p.m. ScottyB New Reader

HiTempguy wrote: er, I don't believe that to be true. The factory manifolds are not equal length afaik, therefore, it WILL sound like a Subaru (just not as aggressive).

well, yes and no. up to '05 the factory manifolds are technically UEL, but barely. with just an axle-back and the stock mani, i didn't find my exhaust note to sound particularly subaru-ish, IMO. i felt it was drastically different with an aftermarket piece.

'06+ are equal-length from the factory, not that it matters for the OP.
Jan. 30, 2011 1:45 a.m. The_Jed Reader

Much like ValuePack, I hacked the stock muffler off of my Brighton and welded a straight pipe in it's place, retaining the stock upstream resonator. There is a video clip in the "reader's rides" section of my profile of me trying to race around a Rallycross course (110hp when new + 130,000 miles ftw) you can watch if you want an idea of how it may sound. It was indeed a bit on the loud and raspy side. Oddly enough I put the same straight pipe axle-back on the wife's L and it didn't have the Subaru bopbopbopbopbop at all...
If I remember correctly the WRX exhaust will not mate up with a 2.5RS exhaust due to the flanges being set at different angles or clocked differently or some such silliness.

http://www.rs25.com/forums/f14/t128072-ms3-wrx-sti-exhaust-adapters-your-93-05-imp...
Jan. 30, 2011 8:59 a.m. Twin_Cam SuperDork

I'll pass all this on, thanks.

Sounds like custom is the way to go...figured that a car with actual aftermarket support would be easier to find exhaust systems for. They do seem goddamned expensive, though.

There is a reputable shop nearby, CSE in Oreland, PA. If she were to bring them say a Flowmaster muffler, does it need to be offset inlet and outlet? Just offset on one end etc etc? What diameter is the stock exhaust?
Jan. 30, 2011 9:40 a.m. DaveEstey HalfDork

Stromung seems to be pretty popular with the RS crowd.

I just put an HKS Silent Hi-Power on my LGT and it sounds amazing, but I'm not sure if they make a setup for the RS.
Jan. 30, 2011 9:43 a.m. Rob_Mopar HalfDork

Twin_Cam wrote:

I'll pass all this on, thanks.

Sounds like custom is the way to go...figured that a car with actual aftermarket support would be easier to find exhaust systems for. They do seem goddamned expensive, though.

There is a reputable shop nearby, CSE in Oreland, PA. If she were to bring them say a Flowmaster muffler, does it need to be offset inlet and outlet? Just offset on one end etc etc? What diameter is the stock exhaust?

I can't remember the exact model I used on my '01. It's been close to a decade. I think it was an offset/center combination. I used a 2" in/out and some bits from the parts store. U-bolts, maybe a bushing on the inlet side to match the Subaru pipe to the muffler. Used a turn-down exhaust tip on the outlet.

If the exhaust shop puts Flomasters on pickups on a regular basis they should be able to knock it out pretty easily. They might need to order the small inlet muffler if they don't want to try and adapt the usual 2 1/2" one to it.

I did fire mine up without the muffler once. It sounded like a big bore Japanese bike. Pretty cool, but would bring too much attention from the local revenuers.
Jan. 30, 2011 12:57 p.m. Twin_Cam SuperDork

And what's all this I keep reading about a check engine light when installing exhaust systems on Subarus?
Jan. 30, 2011 10:45 p.m. flowmann

Just a heads up - Flowmaster is about to offer a new system for WRX - covering 02 through 2011. They use the dBX mufflers. Should be available March 1. For those who don't want to built it yourself.
Jan. 31, 2011 6:06 a.m. ddavidv SuperDork

CEL should have nothing to do with the exhaust system. That is more typical when adding a 'cold air' intake with an oiled filter.

The turbo exhausts do have a different flange angle that must be cut and repositioned if you are using an axle-back setup on a n/a car. Not that big of a deal to have done though. But a lot of people who did that report a not-great sound with that setup.

I bought a Stromung n/a system for our Forester. Sounds nice, not loud or raspy, but with the cavernous Forester interior does make a rather boomy resonance at certain rpm that can be annoying. I was going to have one made custom but didn't want to take the car out of service for a day to have it done, and a used Stromung turned up for a decent price. They are really expensive new. The various message board classifieds are your friend with Subarus, but you have to be quick to claim stuff like this.

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