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Jonnyblaze
01-25-2009, 02:06 PM
Hey, I have a custom 3in catback with a Tanabe Hyper Medallion muffler on my ka24de and above 3k rpm the exhaust is really raspy and sounds pretty bad. My stock exhaust did this too. I'm positive my cat has shit the bed but do you think that is what's causing the sound?

Also, there's a rattling sound above 3k as well. Coming from underneath the car. What could that be?

origin_s135
01-25-2009, 02:49 PM
try 2.5"
YouTube - 240sx 2.5" Megan Racing Exhaust (http://www.youtube.com/watch?v=wAquUIFzrPo)

rattling sound could be a hanger, did u look under the car while it's on?
maybe you have a leak somewhere?

BoostedCoupe
01-25-2009, 03:04 PM
Rattlen could be a hanger, heat shield or many other things. It could be raspy for many diffrent reassons as well.
1. How was it bent? Was it scrushed or mandrel bent?
2. How and where does the catback bend? If it was ran just like the factory exhaust then thats your problem. Look at most aftermarket catbacks, they have as minimum bends as possible.

gyula hlavati
01-25-2009, 03:14 PM
My cat made that sound when I bought my car.I switched it to testpipe and no noises after that.

Rapier46
01-25-2009, 06:46 PM
the sound and "raspiness" is ALL in the shape and resonation of the exhaust. removing cap could hlep, tyr taking out your cat and putting in a oval shaped resonator.

Jonnyblaze
01-25-2009, 07:59 PM
Yeah, it's press bent and is run exactly like the stock exhaust. It was $45 so I'm not really complaining right now. But does the fact that the stock exhaust was really raspy as well mean that something else may be causing the sound?

DMaxUSA
01-25-2009, 11:30 PM
It could be the construction of your 3" inch piping. If you had custom piping made, and welded on a universal muffler, then your exhaust would sound raspy if the airflow isnt smooth.

That's why so many Japanese companies charge more for exhausts. They actually engineer and test their exhaust for airflow and sound quality.

If your raspiness was always there, check your exhaust manifold as well as your cat/downpipe.

gun
01-25-2009, 11:37 PM
^agree-gree^ check your downpipe. Also, make sure there are no gaps where flange meets flange, mine wasnt tight once and sounded like shit allll day until i found the prob, gl

astrophixvox
01-25-2009, 11:48 PM
I had a washer moving around one time on my exhaust and made the whole thing sound like shit. It's probably something small. Get the car on a lift or get under some how and kinda shake things around. If not its your cat.