I just put on the XERD full lenght catless headers with Borla exhaust and got this raspiness or metal rattling at 3500 RPM +. The raspiness is not the pipes vibrating. It is the sound of the exhaust pulsing through the system. It's the muffler that is really causing the sound. The Borla mufflers(baffles) are not sound tuned for the additional sound waves the car now has without the cats(someone told me this). So I'm planning to get magna flow mufflers and replace the Borla's mufflers. Do you think this will work to get rid of the raspiness sound? Any reccomdtion on which muffler size? Any input will be greatly appreciated. Thank you.


Patrick

 

Have then put an in-line resonator put in.

You'll be fine. Hell a stock Z resonator would work nicely.

 

I'm not a guru. But, I am a customer who has driven the Z without the cats. And, from what I've experienced, I'm fairly certain that unless you have a resonator somewhere, either cut into the XERD or afterwards in the exhaust system, you will not be able to get rid of that raspy sound.

In short, unless the Magna flow has a resonator, don't waste your money.

 

Thanks guys!

 

so where would one put a resonator if I have the same problem with my test pipes and stock exhaust (or add a Borla later)??

Do I have it installed in the test pipes???

 

the raspiness is not a problem...

its natural for a tube to have a resonant frequency.. and it just so happens that that resonant frequency happens in the mid 3k RPM range...

 

not for performance, BUT i am not sure I like the sound

 

in general... performance = louder...

I love the way nismo puts it with their R-Tune product discriptions...

"Engineered for the hard-core enthusiast or weekend racer (off-road use). Street "civility" is compromised for maximum performance."

 

true, kind of, but it sounds like there is a way around it by using a resonator.

 

well yes, a resonator will fix the "problem"

BUT, resonators will restrict air flow slightly... and having straight pipes in place of cats is to maximize air flow through the exaust system...

High FLow Cats are what I would recomend for someone who wants a free flowing exaust system but not as loud as test pipes.

I heard a rumor that performance nissan just got a bunch of high flow cats in...

 

The Magnaflow muffler will work without compromising any performance. The resonator will work but will take a bit of power. Plus the Magnaflow will sound better than the Borla.

 

I got the same raspy sound when I had replaced the factory y-pipe with a y pipe with magna flow cats. I think that the stock factory cats kill that resonant frequency.

 

factory cats kill the resonant frequency and air flow...