High Flow Cat + Racing Beat Catback Exhaust Question

Riot_Polizei

Comp Engineering Student
:
2002 Mazda Protege5
Hi folks,

So I'm wrapping up some basic maintenance on my vehicle, and I've decided that it's time to dedicate some cash for the Racing Beat catback exhaust.

Similarly, my cat is also starting to go out, so why not get a more balanced exhaust velocty / scavenging sweet spot if possible? I'm contemplating picking up a high-flow cat as well. Thing is, I absolutely abhor ricey/raspy/buzzy exhaust. Anytime the neighbor fires up his shitcan Civic sedan, I can't help but retch. Talk about second hand embarrassment...

Do any of you know if adding a high-flow cat alongside the RB catback will make the exhaust noise raspy and ricey? It's an oddly specific question for a specific pairing of components, but I really want to make sure before I buy a new catalytic converter.

Thanks!
 
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I have he racing beat cat back, and I also had a magnaflow high flow cat installed on a 2.5" pipe to mirror the stock set up...just a little bigger. It does not sound "ricey/raspy/buzzy", it sounds really good. I don't have any sound clips now.
 
Thanks for the input!

Does your high-flow cat screw with the O2 sensors or provide bad readings, perchance?
 
The primary 02 that is used for running the ECU is before the cat, so it will not affect the tune. It may throw a CEL if you have a 100 cell cat but most cats are 200 cell or higher and you should not have any issues. Can always do the non-fouler mod if you get a CEL with the cat.
 
The primary 02 that is used for running the ECU is before the cat, so it will not affect the tune. It may throw a CEL if you have a 100 cell cat but most cats are 200 cell or higher and you should not have any issues. Can always do the non-fouler mod if you get a CEL with the cat.

Oh shoot, I didn't even think about the possibiility of throwing a CEL with a high-flow cat...

Hopefully, that aforementioned Magnaflow HFC is 200 cells or so, since I'm too chicken to perform more advanced mods like that anti-fouler trick! Otherwise, I'll most likely stick with the decaying cat I currently have.
 
The catalyst 02 sensor only monitors the pre-cat that's just below the exhaust manifold. Unless you install a header and do away with it, a cat back exhaust will not affect it.

The primary cat is not monitored by an 02 sensor and can be swapped with whatever you want.
 
if you dont want that raspy sound, use resonators. just make sure you have at least one resonator somewhere in your setup.

if you get a high flow cat, that resonator will be especially important to help filter out the added rasp.
 
the racing beat already has a resonator... changing from a stock cat to high flow cat isn't going to make much of a noise difference... it'll sound nearly the same
I have 2 high flow cats in mine, with the racing beat.... sounds no different than it was (not like a honda)
 
so what is the point in adding the high flow cats then? as long as your current ones werent clogged, there is no point.

what was the point of this thread by the way? you already have the high flow cats, and you already have the exhaust system. so what exactly was the question?

I'm the original poster, not theMAN

Once I get my tax-return money, I'll go and get a RB catback exhaust. My cat's burnt/burning out, judging by the lovely egg smell, so I'm contemplating getting a high-flow cat along with it.

My question was about the high-flow cat, and whether or not it gives the P5 (after the RB Catback Exhaust installation) a crap ricey exhaust sound.

One member claimed that it's not the case, and I won't get a crapbox noise. I also found a YT video of a guy that had a high-flow cat + RB catback that demonstrated the sound, and it was pretty sweet.
 
I'm the original poster, not theMAN

Once I get my tax-return money, I'll go and get a RB catback exhaust. My cat's burnt/burning out, judging by the lovely egg smell, so I'm contemplating getting a high-flow cat along with it.

My question was about the high-flow cat, and whether or not it gives the P5 (after the RB Catback Exhaust installation) a crap ricey exhaust sound.

One member claimed that it's not the case, and I won't get a crapbox noise. I also found a YT video of a guy that had a high-flow cat + RB catback that demonstrated the sound, and it was pretty sweet.

as long as you have a resonator it wont sound bad.
 
Just want to chime in that I really love my RB cat back system. It's well worth the cost.

I used to have the mazdaspeed etched axle back and it was too loud for my taste just maneuvering in a parking garage and also droning at 65 mph + speeds on the interstate highways.

The RB exhaust sys is about as quite as stock at a highway speed which helps when you're trying to listen to something. My ear detects a slight bass tone when driving around in a normal style. It doesn't bother a sleeping baby in the back and I thing it even helps infant and toddlers sleep more deeply. But if you mash the gas pedal and get the rpm up quick you'll get a proper sport sound coming out. It's great!
 
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