We need a thread to review mufflers available for custom exhausts. There are tons of univerasl mufflers out there, so let the reviews begin.



Borla XR1 - useless on a street car. Actually makes the car louder below 4k rpm, but a good bit quieter above. This is a racing muffler in the truest sense of the word.



Dynomax race - quietest of the straight through mufflers Ive heard. Good tone, good flow.



Magnaflow - The word muffler is a bit of an overstatement on these. Extremely loud, but still quieter than the XR1. Very raspy tone on a n/a if used alone.



Moroso spiral flow - best thing to happen to rotaries since turbos. These make an unbelievable drop in the sound level, and have a very nice, incredibly smooth tone. Somewhat restrictive, but its probably less restrictive that most other baffled mufflers. Also notoriously short lived in n/a's. My solution was to make my exhaust single 3" into dual 3", with 2 of the moroso mufflers in the y pipe. It reduces the restrictiveness, makes the exhaust quiet, and Ill update on the longevity in a few weeks after i get some time on these mufflers.



Edelbrock RPM series - dont even think about it. A friend of mine went through a series of these. Longest life was a week, shortest was 5 min. Yes, he blew the case in half in 5 minutes on one of them. Mostly stock S4 n/a.

weird how most people think the borla is the ****. you wouldn't happen to know about the titanium ones?

Im really happy with my midas replacements. Sounds great with rb down pipe and presilencer. Cant beat $110 can a piece! and lifetime warrenty https://www.nopistons.com/forums/pub...DIR#>/wink.png

Perfect if you dont want to get hounded by cops but still want nice tone.

Borla makes good mufflers, my point ws the XR1's are as advertised: RACING MUFFLERS



I dont have any experience with the Ti ones.

if i may add...



dynomax 3" round tube muffler, i cant find a pic on their site, possibly disco...

on an na ITS FRICKEN LOUD its LOUD ON A TURBO, works well as a presilencer but not good by itself.





magnaflow xl chambered 3" http://www.magnaflow.com/02product/xl/xlchamber.htm

pile of poop but its cheap and with muffler above ok noise level. its very fragile though, it keeps breaking, bearings are shot too....





racing beat 3" preslinecer for turbo cars. expensive but its the quietest best flowing muffler north, east, south annnnnnnnd west of the pecos. it allows you to use almost any other muffler in the back and keep it streetable

there are different borlas, XR1 are straight thru, the Borla system for

the FC is actually very mellow

Bah! The XR-1 is the only thing resembling a muffler in my 3" exhaust, and I can drive the car anywhere, at least in Virginia. Granted, if you have your foot on the floor and you're taching to redline, then you'll make some noise, but an intelligent driver should be fine.



The car regularly passes state inspection with this muffler.

But I will agree, the XR-1 is a bit loud for some tastes. https://www.nopistons.com/forums/pub...#>/biggrin.png

Interesting, lets make this a FAQ soon.

I'm thinking of the hks carbon ti muf. anyone use this and have any infor on sound, tone etc?

its not bad, used with the 3" rb presilencer its not loud, little droney

Moroso Spiralflow worked well for me - I don't think it can be that restrictive because my turbo (60-1) response didn't suffer at all (although I do have a cat

in front of it). It does a good job getting the "boominess" out of the exhaust. I

have a straight through type muffler after it that silences the higher pitched tones.

Dangit, rotary exhausts are so expensive to put together. Any good ideas for a quiet cheap custom catback exhaust or does that not exist?

dynomax and borla sytems

If you want quiet, keep the stock cats. Other than that, that was the whole point of this thread...

ive heard a couple cars with the old (black) rb turbo back and an intake and it was silent, quieter than stock

i want to hear more about that new apexi muffler i forget the name but it has a piston so at low throttle its more restricted and not as loud but when youre at high throttle it opens up completly and is loud and non restrictive

Yeah exactly.



Why do our cars require so many freakin mufflers...



MS7: How much did your entire setup cost you?

The mufflers were about $350, and I spent another $50 on the tubing and mandrel bend I used. I already had the collector from my last exhaust, as well as the header. But both are in the process of being redone and I expect that to add another $100 or so in materials. It took me about 14 hours total to do that exhaust as it is now, and Ill probably put another 8 hours into the new header. I cant wait to have a vband instead of that cursed 6 bolt flange RB uses on their headers.

haha, thats a lot of fun isnt it

I have "a cat" (a Random Technology main cat). Using the RB header, that cat, and the OEM muffs - above 4500 RPM it's unbearably loud. The RT cat does absolutely nothing for noise suppression.



My son can literally hear me from half a mile away. Can anyone assuredly say that $400 worth of RB NA cans quiet it down, or is it a lost cause? I have to keep at least one cat. The state of California has a unique way of meeting the "budget crisis" - fine the hell out of you for any infractions they can. Is it just me, or is there something wrong with the term "infraction" being synonymous with a $1500 fine?