Quiet Muffler

[AlcyoneDaze]

Hi, I'm going to do a dual muffler setup in my SVX and I need two good mufflers.

My definition of good:

low-priced, since i'm buying two, this is a must, sub-$200 per piece
rust-proof, no MONZA
quiet, preferably no louder than the stock SVX exhaust, but a low-rumble would be nice
high-flow, want to actually improve performance and reduce backpressure

[svxistentialist]

Hi, I'm going to do a dual muffler setup in my SVX and I need two good mufflers.

My definition of good:

low-priced, since i'm buying two, this is a must, sub-$200 per piece
rust-proof, no MONZA
quiet, preferably no louder than the stock SVX exhaust, but a low-rumble would be nice
high-flow, want to actually improve performance and reduce backpressure

Best of luck with this Alcyone. I'm with you on the sound, a quiet deep rumble is what I prefer too.

I had a magic JDM aftermarket exhaust on my Legacy Twin Turbo. Deep soft rumble.

One thing to be careful about; you say you want to improve performance and reduce backpressure. If you car is not blown or turbo'd you may make low speed driving erratic if you reduce back-pressure by too much.

Reducing back-pressure will let it breathe better at high revs, important for racing cars. However the pressure and resonance of the outflowing gas is balanced by the exhaust and resonator to maximise gas velocity at low revs. If you free it up too much, your idling will go lumpy like a racer's.

The above only applies to NA cars, like the standard engine. If your engine is pressure fed, then the freer the better.:)

Joe:)

[Hocrest]

SVXfiles is working on a new setup right now. From talking to him the sound and performance meet your needs. But we didn't talk about price?? You may want to send him a PM.

[svxfiles]

SVXfiles is working on a new setup right now. From talking to him the sound and performance meet your needs. But we didn't talk about price?? You may want to send him a PM.

Dave, that system was SO QUIET, evan with 2" headpipes and 2"X2 in and
2.5" single out cat it was quieter than stock!!!
AERO AR20, at $82.00 each plus shipping, (VERY FAST SHIPPING) do a great job of quieting down the exhaust.
For true duals, don't go ovet 2", and you will prob need 4 resonators total.;)

[SVXRide]

Dave, that system was SO QUIET, evan with 2" headpipes and 2"X2 in and
2.5" single out cat it was quieter than stock!!!
AERO AR20, at $82.00 each plus shipping, (VERY FAST SHIPPING) do a great job of quieting down the exhaust.
For true duals, don't go ovet 2", and you will prob need 4 resonators total.;)


Note for folks who don't check Tom's extensive photo archives -- the AERO pieces are used in place of the stock primary cats.:cool:
-Bill

[svxcess]

the AERO pieces are used in place of the stock primary cats.
svxfiles seems to think that this is THE exhaust system. I have already committed to getting him to install this system on my 1996 polo. Harry's system does not have the stock resonator behind the third cat, just a straight pipe. Adding another Areo resonator will quiet it even further.

I will be going up to Tom's on Wednesday morning to check it out in person.

http://www.subaru-svx.net/photos/files/svxfiles/41691.jpg

More photos in his locker, starting around photo #50, can be found HERE (http://www.subaru-svx.net/photos/user.php?svxfiles|40818)

.

[ensteele]

That looks like a great system. Maybe a sound bite could be taken so we can hear what it sounds like. :)

[svxfiles]

That looks like a great system. Maybe a sound bite could be taken so we can hear what it sounds like. :)
It IS a great system, BUT, with the stock SVX muffler, NO factory resonator it is as quiet, or quieter than the stock system!
It just flows more!
Tonight I did the Madder Muffler Mod, to increase the sound, and flow of the factory muffler, (in that order) and it DOES give the exhaust note more bite,
but it is STILL not objectionable.
Stop in by Wednesday for a listen/drive!:D

[svxistentialist]

It IS a great system, BUT, with the stock SVX muffler, NO factory resonator it is as quiet, or quieter than the stock system!
It just flows more!
Tonight I did the Madder Muffler Mod, to increase the sound, and flow of the factory muffler, (in that order) and it DOES give the exhaust note more bite,
but it is STILL not objectionable.
Stop in by Wednesday for a listen/drive!:D

Quieter than standard sounds good to me.:rolleyes: :rolleyes:

Is it less restrictive than the standard system? Will it flow enough gas for a 300-350 hp blown engine?

Joe:)

[Ricochet]

I have yet to hear an aftermarket svx exhaust system not sound raspy. I'm going to stay stock until something's tried and true.. keep us updated.

[TomsSVX]

Shotgunslade's car is not raspy. His exhaust setup is the best N/A I have heard to date... Just the perfect tone and the perfect volume. The shop that did his is near by (within an hour's drive). If you want I will try and get some audio of his when he is here Sunday and if you like it, I will drop your car off at the exhaust shop for a dupe

Tom

[Ricochet]

Yeah a shot of him driving under full throttle from the outside of the car would be cool.

[TomsSVX]

I will see what I can do but we can get some standing still audio for sure

Tom

[benebob]

I have yet to hear an aftermarket svx exhaust system not sound raspy. I'm going to stay stock until something's tried and true.. keep us updated.

No rasp with our SVXfiles setup. Granted its just under the 96 decibil limit for most tracks.:D

[SVXRide]

No rasp with our SVXfiles setup. Granted its just under the 96 decibil limit for most tracks.:D


What? What? I can't hear you...:rolleyes: :p
-Bill
p.s. the sound is even louder when it's echoing off of a brick wall...

[benebob]

What? What? I can't hear you...:rolleyes: :p
-Bill
p.s. the sound is even louder when it's echoing off of a brick wall...

Different exhaust Bill, it didn't go on until just before the Subie challenge. Definately a much better sound although I don't think it has quite the low end grunt it did with the old tin can sound. Now it just scares away the competition.

FYI Dave's got the $$$ in his account now so we should have some details on the cage. Only problem is the Racer is plowed into a corner in the storage lot with 5 feet of ice in front of it and I'd need to drive my SVX out into 7 inches of ice which will probably be there til the end of March. Lots of welding to do!

[svxfiles]

Is it less restrictive than the standard system?
Will it flow enough gas for a 300-350 hp blown engine?

Joe:)
Yes. MUCH less restrictive.
And for your second question, no.
All though it is great on midly built stuff, up to about 260 or so hp.
Our stock system narrows down to 1.6" after the pre cats, and this one is never narrower than 2" od.
I have a system that ends with a 3" od on a ported and blown SVX, and it would be to big, without the blower.
Too big kills the bottom end.

[svxistentialist]

So If I hear you right, no narrower than 2" is ok for 260 hp or so.

In that case, would my requirement be answered by 2.5" pipes?

And if so, if correct, would this also dictate that the headers need to be larger also?

Joe

[svxfiles]

So If I hear you right, no narrower than 2" is ok for 260 hp or so.

In that case, would my requirement be answered by 2.5" pipes?

And if so, if correct, would this also dictate that the headers need to be larger also?

Joe
THIS system if fine for 260/270 hp.
It consists of;
TWO pipes of 2" for the headpipes, an expantion event, in the form of a resonator, muffler, or cat, or pre-cat where the stock pre-cat goes, followed by two 2" pipes back to a Magnaflow two into one cat with a 2.5" outlet is what we have on the latest in a very long series of muffler systems.

Headers is a much easier answer.:)
1,5/8" primarys, 30" long, into a 2,1/2" (2,11/4" is ok too) collector about 10" long.
And for drag or wide open racing, either a twin 2,1/2" dual or a single 3" with
strait through mufflers or resonators.

Mandrel bent is best, stainless steel holds more heat to speed up the speed of sound creating better scavenging.

Unless you are going to supercharge, or turbocharge, or run big NOX, 2" from the factory headers back, and at least 2.5" after that is big enough, and not too big.
This link gives an idea, but it is certainly not the last word.
http://www.angelfire.com/my/fan/Exhaust_Pipe_Size.htm

[svxistentialist]

Thanks for the excellent detail.. This is what I need to base decisions on.

I am supercharging with an Eaton M110. That is why I mentioned 300-350 hp.

I mean that as flywheel HP, not at the wheels. I want a mild upgrade because I am retaining the auto.

I obviously need it to breathe well, so upgrading the exhaust is an important change. However, and this is a biggie for me, I want the car to be as quiet as stock, or quieter.

I'm aware most people upgrading the engine may want their car to sound like a Nascar racer or something, to let people know they have hair on their chest or whatever.:rolleyes:

Not me. I want to hear the stereo.;) So bigger is good, if bigger is quiet.

Joe:)

[svxcess]

Tom and I are working on a modified version of Harry's exhaust system. For the time being, we are keeping it under wraps and, if all goes well, it will allow for an increase in power and exhaust flow, while allowing the car to a lot quieter than the original factory system, under acceleration

It will be a mostly weldless system. There may also be a subtle modification of the stock exhaust tips to give them more of a stealth look.

This looks to be the most expensive configuration yet, short of a Stebro system, but all of the parts are top quality. If I decide to go ahead with it, I will have done by Reading.
.

[svxistentialist]

Tom and I are working on a modified version of Harry's exhaust system. For the time being, we are keeping it under wraps and, if all goes well, it will allow for an increase in power and exhaust flow, while allowing the car to be virtually silent under acceleration (or at least a lot quieter than the original factory system)

It may be a welded system, but a weld-less alternative is available. There may also be a subtle modification of the stock exhaust tips to give them more of a stealth look.

This looks to be the most expensive configuration yet, short of a Stebro system, but all of the parts are top quality. If I decide to go ahead with it, I will have done by Reading.
.

Sounds good John.

I'll be interested in seeing that.

Graham in England has a custom set-up on his, dual stainless pipes all the way back. He does not have a cat in the system, and I would have to have my car clean.

So clean and quiet and breathing deep is my goal.

Joe

[AlcyoneDaze]

You guys are crazy in a good way :p

I'm thinking just running two, 2" mufflers sticking straight out the rear, where the tips currently reside, no resonators or anything fancy and expensive. What I'm really after is a sporty muffler, 2" diameter, that is quiet in and of itself.

[svxcess]

My stealth exhaust system is arriving at svxfiles and all parts will be there bty this weekend. Installation is scheduled from Sunday through Monday.

As I said, it is modified version of Harry's (newsvx) exhaust system. it should allow for an increase in both power and exhaust flow, while allowing the car to be virtually silent under acceleration (or at least a lot quieter than the original factory system)

Except for welding the new modified flanges to the larger pipes that connect directly to the exhaust manifold, it will be a weldless system. Nine special stainless steel connectors will be used to insure a leak-free connection, which will be as good as a welded system. The only other weld is relocating the third O2 sensor (OBDII) from its normal position for easier access.

If we have time, there may be a subtle modification of the stock exhaust tips to give them a more stealth appearance.

This will be all done by Reading. I will post a teaser pic or two as it is underway.
.

[svxfiles]

One package came today, John.:D
http://www.subaru-svx.net/photos/files/svxfiles/42417.jpg
:cool:

[svxcess]

Well, that's most of the system. Maybe the rest will come in tomorrow.

Now all we need are the larger head pipes and the flanges. As I said, this photo of Harry's car is the basis for the front part of the system.

http://www.subaru-svx.net/photos/files/svxfiles/41691.jpg

This is sure going to be pretty system though. If I was true to sv-xcess form I would have had all of the exhaust piping alumi-ceramic coated to match... :D
.

[Hocrest]

This is sure going to be pretty system though. If I was true to sv-xcess form I would have had all of the exhaust piping alumi-ceramic coated to match... :D .

Do they make Polo Green in Hi-temp?? :D :D

[svxfiles]

Do they make Polo Green in Hi-temp?? :D :D
Thanks Dave!:mad: :rolleyes:






It's actually a GREAT idea!:)
That way roadkill and mechanics will have eye candy.:rolleyes:

[SVXRide]

Thanks Dave!:mad: :rolleyes:






It's actually a GREAT idea!:)
That way roadkill and mechanics will have eye candy.:rolleyes:


goes nice the the neon you're going to wire in, right?:rolleyes: :p
-Bill

[svxfiles]

http://www.subaru-svx.net/photos/files/svxfiles/42547.jpg



Tired Tom.:o

[svxfiles]

http://www.subaru-svx.net/photos/files/svxfiles/42548.jpg
:)

[svxfiles]

http://www.subaru-svx.net/photos/files/svxfiles/42550.jpg
:p

[TomsSVX]

FREAKIN SWEET!!!!

Tom

[svxfiles]

FREAKIN SWEET!!!!

Tom
Thank you Tom.:cool:

[svxcess]

It's Done!!

svxfiles once again did a magnificent job on this, (even under the close and unrelenting scrutiny of the sv-xcess!)

The system is pure eye-candy and Tom firmly believes that this is THE ULTIMATE exhaust system for the SVX. The entire system, except for the aluminized exhaust tubing and stainless steel catalytic converter, came from Verocious Motorsports. The Magnaflow 94037 high-flow catalytic converter is from Performancepeddler.com

The Torctite clamps (http://vertexnow.com/Verocious-Motorsports/Torctite/TorcTite-Stainless-Steel-Exhaust-Clamp) work perfectly. Stepped, solid stainless steel , 360° clamps with grade 8 bolts let you tighten them to make leakproof connections. All of the aluminized piping was further re-coated with an aluminum ceramic exhaust coating rated at over 1200°

The system begins with full 2" diameter pipe welded to new exhaust flanges coming straight back from the headers, then into the two polished stainless steel Aero Turbine AR20 resonators (https://aeroexhaust.com/i-30497602-aero-exhaust-resonator-ar20-ar-series-2-inside-diameter-necks.html) with 2" inlets, that replace the front cats. The 2" tubing exits from the rear of the resonators and into the Magnaflow high-flow catalytic converter.

From the rear of the converter, tubing is now 2.5" (with the third O2 sensor tapped directly into the pipe behind the converter for more accurate exhaust analysis and easier changing.) The 2.5" pipe then goes directly into another polished stainless steel AeroTurbine AR25 resonator (https://aeroexhaust.com/i-30497603-aero-exhaust-resonator-ar25-ar-series-2-5-inside-diameter-necks.html), in place of the stock resonator and 2.5" piping all continues the way back to the factory muffler.

The new exhaust system has more flow and a much gentler flow path and less restriction than the stock system. It also sits a lot higher than the stock system as well, tucked up out of the way. No leaks, rattles or strange noises. Everything is rock-solid and beautiful!

We had to replace one of the front O2 sensor that the Subaru dealer had installed without anti-seize compound. We removed it from my stock system with a great deal of difficulty and found there were no threads left on it to reinstall it into the new bungs that we welded into the new system. So now we have an efficient, simplified system with 3 resonators, 1 converter and a muffler.

The car started right up and ran very smooth, extremely quiet and strong. No codes or check engine light. We had toyed with the idea of adding yet another 2.5" resonator between this one and the rear muffler, but decided that would be overkill!

More photos in svxfiles locker HERE (http://www.subaru-svx.net/photos/user.php?svxfiles|42516) I will put more updated photos in my locker after I get home. I will also report on how the car performed on my return trip to Baltimore from Tom's later this afternoon



Its now 3:30am, Tom was in bed hours ago, but is now back up and guzzling wine (In Wiley Ford, it seems Asti, like Tang, is more of a breakfast drink) :p

All and all, its been a most EXHAUSTING day! :D

[svxfiles]

It's Done!!

Tom did a magnificent job as always. The system is pure eye candy and Tom agrees that it is THE ULTIMATE exhaust system for our cars. The entire system, except for the exhaust tubing, came from Verocious Mororsports (http://vertexnow.com/Welcome-Verocious-Motorsports)
:D
The two into one Magnaflow cat came from
performancepeddler.com
;)
I am very happy with this system.:)
Especially the NEW FREAKIN HEADPIPES!!!!!:D :cool:

It's just a shame it went onto a car that will not see over 6500RPM!!!:eek:
:p












Slowpoke!

[svxcess]

I am very happy with this system.:)
Especially the NEW FREAKIN HEADPIPES!!!!!:D :cool:

It's just a shame it went onto a car that will not see over 6500RPM!!!:eek:
:p

.............

[TomsSVX]

Hey Tom, how much do those cats cost from there?? I know where you can buy em for more:D :D :D :p

tom

[benebob]

It's Done!!

svxfiles once again did a magnificent job, (even under the unrelenting scrutiny of the sv-xcess!)




Well my eyes may deceive me but that thing is far from done. Once John spends the next month polishing it to a mirror finish then it will be done!;)

[shotgunslade]

:eek: Momentary thread hijack

Tom (SVXfiles): You have PM.

Dan

Returning thread to its proper owners. ;)

[SVXRide]

I don't know....it looks like the right and left sides aren't perfectly parallel....:p :D

-Bill

[svxcess]

Took the car out for its first test drive at Tom's this morning. Had a CEL on the dash, probably from running the car last night without the third O2 sensor installed). Cleared the code and all was fine.

During our initial test run we had an intermittent misfiring in one of the cylinders, which would cause car to run really rough at times (especially at low speeds with the TC locked up) Tom's subaru monitor confirmed that the problem was a misfire in cylinder #3. This was not a result of anything that we did, just a coincidence.

We replaced the coil pack (which turned out to be the problem) along with a new NGK plug (which was one of the original ones with 101,000 miles and looked perfect). After that we cleared the codes, ran the diagnostics and all was well from then on

This exhaust system performs exactly as Tom predicted. Better exhaust flow and velocity at higher speeds and much quieter as well. The faster I went, the quieter and more responsive it was. Tom still considers this setup the optimal exhaust system for the SVX (having gone through a dozen different configurations) The *new* exhaust system for his supercharged is loosely based on this system, only increasing the headpipe diameter from 2" to 2.5". That's all I'll say.

With the stock exhaust system, I could hear both the engine and the exhaust at 85mph. Now I am only aware of the engine at that speed. It definitely has more pulling power at the higher speeds under load (such as climbing a steep hill while in Drive, without having to downshift).

One unexpected side benefit seems to be improved gas mileage. I filled up in Baltimore before going to Cumberland. By the time I reached Tom's house, the gas gauge read halfway between the 1/4 and 1/2 mark on the gas gauge

On the return trip I filled up in Cumberland and travelled the same distance back to Baltimore, When I got here, the gas gauge was reading a hair above the halfway mark.

I will keep more detailed records on this and report back with the findings.

I may also try to put my photos of the system in my locker tomorrow.
,

[benebob]

One unexpected side benefit seems to be improved gas mileage. I filled up in Baltimore before going to Cumberland. By the time I reached Tom's house, the gas gauge read halfway between the 1/4 and 1/2 mark on the gas gauge

On the return trip I filled up in Cumberland and travelled the same distance back to Baltimore, When I got here, the gas gauge was reading a hair above the halfway mark.

I will keep more detailed records on this and report back with the findings.

I may also try to put my photos of the system in my locker tomorrow.
,


Are you sure that the better g. m. wasn't from going down hill? System looks fairly light. Any adverse handling effects by raising the center of gravity a bit? Really when does the polishing start?:D

Might want to have the front portion ceramic coated which would increase flow a bit more!

[svxcess]

Are you sure that the better g. m. wasn't from going down hill?

Every time I drive back and forth to WV, I notice the hills go up AND down. Maybe the route you take are all uphill one way and all downhill the other.


System looks fairly light.

We never weighed it, but moving both the stock and complete systems around, there IS a definite weight reduction


Any adverse handling effects by raising the center of gravity a bit?

I don't think so. It is tucked up higher and out of the undercar windstream, which should keep it hotter. maybe that was also one of the reasons for our heat shields in the first place.; to insulate the front pipes and and keep under car air from cooling them too much

And any road-kill that is under the car is cooked only to medium instead of well-done. Parking on grass without heat shields in place should be better.


When does the polishing start? :D

I'll get to Reading early on Thursday, jack the car up and put it on 2' jackstands and get under it with my 6 cans of Nevr-Dull and my gas-powered portable buffer. Might be a good time to Dremel my S/S lines as well. I might leave it on jackstands all weekend ;)


Might want to have the front portion ceramic-coated which would increase flow a bit more!

Then the color wouldn't match the rear pipes, so I would have to colormatch them... then that color wouldn't match my wheels, so I would have to redo them.... then the wheels wouldn't match the... you get the idea.

I wonder if the Flowmax® capsules my urologist gave me would work if I dissolved them in some fuel injector cleaner and added it to the gas tank? Sure improved my flow a bit more. :)


....................

[svxcess]

As promised, I have uploaded photos of the EE/3 (Expansion Event x 3) exhaust system into my locker
http://www.subaru-svx.net/photos/user.php?svxcess

But first a couple of teaser photos to get you started...

http://www.subaru-svx.net/photos/files/svxcess/42615.jpg

http://www.subaru-svx.net/photos/files/svxcess/42603.jpg

http://www.subaru-svx.net/photos/files/svxcess/42600.jpg

http://www.subaru-svx.net/photos/files/svxcess/42604.jpg

http://www.subaru-svx.net/photos/files/svxcess/42594.jpg

.

[sperry]

So, when is this thing for sale? ;) I've got a case of the exhaust rattles under the car, and money in my pocket!

...actually, my stock muffler is kinda beat too. What's would it take to build a header thru cat version of this so I can bolt a Stebro cat-back to it and really blow a bunch of cash on my exhaust? :devil: