okay guys i installed my obx headers/ypipe a month ago and ive noticed that between 2-3k rpms that a raspy sounds come out as i accelerate i can not stand the noise to me it sounds ricey although on higher rpms on the highway it sounds good.. my mods are listed below the Megan is on the way but what could be the problem ? The noise came after the headers were installed.

 

That's what happens with a test pipe and headers/CM midpipe. I'm not familiar with the Megan, but does it have a resonator?

You need a resonator. Or a Catalytic converter.

 

right now i have on a 2.5" ebay catback and i replaced the catalytic converter with a custom maxima high flow cat but the ebay catback did not come with a resonator.. so will i hear that raspy noise with the new Megan catback ?

 

I dunno, does the Megan have a resonator and is the Custom Maxima cat actually a cat or just a resonated pipe?

That's from the website, and that's the cause for the rasp.

 

Yep thats exactly it, so what can i do then ? go catless ? buy the stillen high flow cat ? buy a resonator ? or will the Megan be the solution ? im not positive if the Megan has a resonator.

 

I would get a Fastcat from Cattman.

I've run catless for years, bu I just don't like the sound or the smell. I had to add a bunch of resonators just to get rid of the rasp, sorta sucks when you hack up your cat-back just trying to rid the rasp.

The Cat will also eliminate the 78 Chevy smell at the same time.

 

ehh im not crazy about the resonated fastcat im going to get the Megan installed i just called they said it comes with a resonator so if its still raspy ill just go catless.

 

Resonated Fastcat....?

It's an actual catalytic converter, not just a resonated pipe like what you have on there now, and it's cheaper than an OEM cat.

 

you have a link ?

 

Nope, but I have a Fastcat. Call Cattman and ask him for details, since his site isn't really up to date.

 

okay thanks ill do that, but what do you think about going catless ?

 

Going Catless is not going to help your situation any. Six unrestricted cylinders, no matter the configuration (V or inline) tends to sound raspy. Unless of course you do what a few on here have and add extra resonators or bigger mufflers.

The Cattman piece is likely your best option for performance.

 

damn alright i guess that is what i have to do, i sent them an email.. how much did you get yours for ?

 

The OP is already cat-less.
Here's my take on it:

 

They run about 225 if not mistaken I was going to go with the CM 50 bucks also but went the other route CATTMAN!!

 

well it looks like you were the smarter guy huh ?

 

CM is a test pipe, so yeah, not a cat at all. Will do nothing for rasp.

 

so Cattman fastcat it is.. hopefully i wont even need it when i install the Megan catback since it has a resonator on it

 

??? all catback comes with a resonator

EDIT: unless you bought cattman and requested no resonator

 

Resonator or not, it's the test pipe that gives the rasp.

 

The test pipe doesn't actually create "rasp" - it just doesn't do anything to quiet the characteristic sound of an even-firing 6-cylinder engine. A real high-flow cat will help at least some.

Splitting the exhaust after the cat into two pipes and choosing the mufflers with a little thought toward noise levels (I'd seriously consider using two OE mufflers) will help still more. The fact that you'd have two mufflers in parallel and sharing the flow means that you'll still be ahead of the stock OE arrangement as far as backpressure is concerned.


FWIW, "rasp" is really too negative of a word to be using for describing the sound that a good IL-6 or V6 makes naturally - true rasp is what you get if a muffler baffle weld or two fails and the muffler internals start buzzing around inside at various rpms. You simply aren't going to get a heavy V8-ish rumble to come out of these cars no matter what you do with the exhaust (or anything else short of actually swapping the V6 out and a V8 in).


Norm

 

So it doesn't create it, it allows it. My bad.

2 OEM's under an A33 chassis. Talk about space requirements.

 

no they dont my ebay catback did not come with a resonator i had already checked.

 

Custom Maxima advertises a $50 test pipe that provides "10-12 HP Gain For the Maxima"?

That's some magical test pipe.

Imagine building an entire business around the principle "Caveat emptor", with the premise that your customers don't speak Latin.

 

get a cherry bomb resonator...or any decent long resonator (length depending on how much noise you want) but adding a resonator to my setup made it PERFECT!

 

When I first installed my headers, I didn't even want to drive my car the rasp was so bad. I literally parked my car, and refused to drive it for a few days.

After adding a 23" cherrybomb, my car sounds amazing. If you are already getting the meagan catback, I would wait till you have that installed to make your decision on testpipe vs. fastcat.

just my $.02

 

i agree with you 100%.. where can i get this cherrybomb resonator ??

 

www.summitracing.com

I rocked a 22"x4" (2.5" in/out) unit

 

Fallaces sunt rerum species

 

Just make sure you order one that has a perforated core, rather than louvered.

 

take a pic

 

I installed a Cherry Bomb glasspack on my 3rd Gen and wow it's rather quiet with a slight burble........

 

Perforated > louvered ... I lost some airflow going with louvered.