No Cats + No Resonator = HORRIBLE

smithers_0990

On and On
:
02 P5 & 01 Audi S4
I removed my last cat today. What a bad idea. I made an appointment to get my resonator put back in.
I hope that will take care of the noise.

My car sounds like a HOOPTY now. And it smoke comes out of the engine bay from the WD-40 that I sprayed on the bolts to get them off.

(hand) Why did I do that.(boom07)(ricer):'(
 
what kind of muffler do you have? a resonator and good muffler will do wonders for you if you want to go catless, but you'll smell really foul.
 
Spray (when the engine/piping is COLD) some non-chlorinate brake cleaner on the areas that have WD-40...it should take care of it.
 
I could have told you this. My car is CRAZY loud, and I have a cat and resonator. But it's 2.5" exhaust. I couldn't imagine how loud it would be without them on. Not to mention how bad it would sound. Right now it's loud, but it sounds awesome. Honestly, I can't believe I haven't been pulled over yet (boom05)

My advice, unless you're going hardcore, get 2.25" or smaller. Keep the cat, keep the resonator.
 
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I just took it for a long drive, so the wd40 is gone. I have the Mazdaspeed axel back for those of you who want to know. Hopefully she will sound better tomorrow.

I think (after its warm) it smells like a race car. Yes I went and smelled it.
 
I should be taking my last cat off in a few days, hopefully it wont sound too too bad with my 2.25" piping. But knowing that u have the Mazdaspeed axleback makes me wonder, since that exhaust is actually quiet compared to mine (boom07)
 
Its not that much louder than before, its just more raspy. If it was a track car I wouldnt care, but its not.
 
O i see.....i wish i had sound clips of the forum member "equinox" to show you, he has 2.5" piping from the header back with an HKS exhaust...and no cats. I can hear his car coming from like a half a mile away! Its freakin crazy, but its all good for him i guess since his turbo should be in any day. I kind of want the loud sounding noise, but with non of the raspyness.....but i know its up to the exhaust i get.
 
My car is crazy loud even with the turbo, one cat, and an HKS Hi-Power muffler...I could only imagine what catless and no turbo would sound like
 
my exhaust was catless when i bought the car. it sounded and looked like hell. it had an hks titanium muffler. nasty and really loud.

i had it fixed shortly after buying my car (but not soon enough, it drove me crazy.)

my exhaust sounds great now. i love it compared to what it was. it sounds nice and low and not too loud. i will try to get a sound clip for you people.
 
Dude I'm telling you follow my Exhaust layout and your car will not sound like a hoopty. My exhaust sounds sweet and it was pretty cheap to put together
 
Matthew said:
you think youve got it bad, try running an open dump!
i had an open wastegate, with NO dump tube. that was the first thing i needed fixed when i bought my car. i will not even tell you how much that sucked.
 
I got it at some exhaust shop. I had it welded in before I got the cat and RB muffler. With the setup I have now it probably isn't necessary at all since there is quite a bit of muffling action done by the RB axle back.

The reason it is raspy sounding is because you don't have a matrix that diffuses the exhaust pulses. Not only does the Cat reduce emissions but the putting of a spongy matrix makes the car sound a lot better. Just think of a bunch of gases as prticles with vector velocities. When it hits the cat they both react and bounce off in all different directions. This is how it makes the car lose its raspyness. The resonator will do this to a small extent but I really suggest putting a cat in the exhaust stream because it isn't straight through like the res.
 
twizyours said:
Wheir did you get the magnaflow resonator from?
i bought the thermal r&d muffler and tip myself. then i took my car to mufflex in trenton, nj and they gave me a magnaflow carsound hi-flow cat and a magnaflow resonator, and 2.5" custom 304 stainless from the flex tube back.

wagner motorsports is fixing my downpipe to be 2.5" as well.
 
roni said:
i had an open wastegate, with NO dump tube. that was the first thing i needed fixed when i bought my car. i will not even tell you how much that sucked.
umm, did you burn anything like that, thats pretty dangerous, purpose of a dumptube is to keep the exhaust away from s***...my p5 is pretty loud with open WG and open downpipe, sounds like a dumptruck(especially when the turbo spools lol)
 

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