muffler advice

[stefan]

well i worked on my exhaust today. i think ive fixed all the leaks but its still really loud!? well i took my muffler off, and a few pieces of this black honeycomb stuff fell out, and i can hear more rattling around inside. I assume my muffler is shot? any recommendations on a new one? i want it quiet as possible, but reasonably priced.

[xanthinic12]

isn't honey comb pieces from the cat? im not sure and since your upgrading everythingg else might aswell put on a larger diameter exhaust, i have a borla its pretty loud, safteyguy has larger exhaust and its still quiet but i don't remember what company it is

[stefan]

i dont think so, ive looked inside my cat and from both ends it looks like metal mesh/screen inside.

when i said fixing leaks, i mean welding in adaptors/couplers to patch rusted out spots and such... LOL no upgrades goin on here. just looking to get her quiet again. right now it sounds like a tractor.

for now all i need is a sealed & functional exhaust to pass safety and to get by. within a year im goin b6 at the very least, and at that point ill redo the exhaust properly.


oops, how did this end up in custom drivetrain? sorry, maybe someone could move this to repair.

[packrat427]

Yes that is the internals of the Cat. It looks like a small/fine honey comb , It may be brittle and cause a dust when messed with .
The rattle is the remaining pieces in there .

I just had a 2.25 Magnaflow cat put on mine.

[Safety Guy]

If it will help at all: I have a 2" pipe system with Magnaflow low restriction cat and muffler; all 2" connections. The muffler is a straight-through design. I may switch it to an offset Magnaflow muffler to see if it's quieter.

This is on my B6/ATX car.

I'd check your cat to see if it's disintegrating and spewing honeycomb crap out your muffler.

Karl

[stefan]

Yes that is the internals of the Cat. It looks like a small/fine honey comb , It may be brittle and cause a dust when messed with .
The rattle is the remaining pieces in there

odd. when i had my car off i was playing around with it and i thot the stuff inside the cat was flexible.

but what you just described is what came out.

and i just looked up how mufflers work and its obvious that it isnt from the muffler.

is there any way to test a muffler? also, any good ways to find exhaust leaks? because my car isnt much quieter than when the mid pipe was cracked off behind the cat.

[Pu241]

Actually, a lot of mufflers use a diffuser made out of metal with hexagonal array of holes in it!
This array is larger than the array in the cat.
I think that's what he has in his muffler!

Pu241

[packrat427]

^^ I am not sure , Does it break up into fine pieces and seem very dirty to handle , dusty .

How big are the pieces that you found ?

[stefan]

well it was a long day, ill post pictures tomorrow.

the pieces were about 1"x1" ish and they had square veins running thur them.. like honeycomb except square. they were black like charcoal and crushed into dust with a loud crunch when stepped on.

[packrat427]

That is for sure from the cat , they never used anything like that in the mufflers .

Make sure you do not breath that dust from that stuff , converters contain a catalyst made from a noble metal such as platinum, palladium or rhodium.

[WmWatt]

Mufflers rust from inside out. I've taken mine off and dumped a lot of rust out of it.

If the car passes the emissions test it doesn't need a new converter. I've posted here before about the scam a lot of repair shops run telling people they need a new converter. Every time I take my '89 into Midas for a new muffler under the lifetime warranty they try to tell me I need a new converter. The car just passed another emissions test with flying colours in May.

[Gforcefd]

Just because it is passing emissions doesn't mean that your cat isn't getting clogged up.

[stefan]

no emissions tests here! yee-haw!


heres one of the pieces that fell out

[Pu241]

Just because it is passing emissions doesn't mean that your cat isn't getting clogged up.

How so!
If it passes emissions it means:
HC's are in spec and engine is not running rich!
NOx and CO are in spec and emission systems including cat are OK!

Clogged up with what?
Only thing I can think of is if running rich and covering catalytic material with carbon, but then, you'd not pass emissions either!

[Pu241]

heres one of the pieces that fell out

Yeah, cat material!

Pd/Ru catalyst on ceramic support!

Maybe during your exhaust work it was dropped or struck by a hammer!
Ceramic is good for high temperature but brittle.