BHR Midepipe: highflow cat or no?
 

Hey guys, just trying to get an opinion on the highflow cat that comes with the BHR midpipe? I'm going to buy one and don't know if I should get the option.

Depends what your looking for in sound.

Whats your concerns?

if you don't want to be catless then get the highflow

Are you concerned with sound?
Smell?
What are emissions like where you live?

As long as you have the stock cat, you don't need the hi-flo cat in my opinion. When it's time to get emissions testing, just swap the stock cat back on there. Actually, depending what county you live in Texas, you may not need a cat at all (depends if they run the sniffer test).

I have the BHR pipe with no cat and it's hardly loud, a cat would probably muffle that sounds just a bit more.

Yea I live in Texas. I'm not worried about the smell. My stock cat is fried, and I'm not wprried about putting it through the emissions test seeing as I have to go around it already.

FWIW plenty of flow with the Davesport CAT. There is still some smell but not has bad as a resonated or straight pipe. No CEL either so there should not be issues with passing an emissions test.

Yeah man that dyno vid was sweet :D:

For me it comes down to how much power is lost by having the cat in this mid-pipe. I found it interesting that a recent Modified Mag article on their RX-8, the mid-pipe they used actually gained a hp or so when the cat was put in, basically indicating that the cat caused no loss in power. If that's true of this mid-pipe, to me it's a no-brainer: I'll take the one that keeps the car reasonably clean and no CEL.

BHR, do you have an idea on what the difference in power is between cat and cat-less mid-pipe versions?

^^^^ I'm about to buy a BHR midpipe so I'm interested on the answer for this question too.

from what I know... the cat they use is pretty free flowing so the hp difference will not be that substantial...

if you're upgrading just go catless... its what the cool guyz do

The only real benefit of the high-flow cat will be a reduction in the smell, which is the reason I got mine. I doubt it'll reduce emissions enough to pass a test, but I suppose it's possible if your area's standards are very low.

CA has VERY high emission standards, I'm about to install a davesport cat on my car and have a smog test done just to see if it'll pass. I'll let you guys know in the next 30 days or so...

The Davesport Hi-flow CAT they use doesnt really rob any HP from what ive read and what Charles has said. The RX8 doesnt flow enough air to make a difference with the Davesport CAT or not, so it has no differenence really, thats what Charles has said, im just repeating his words :)

FWIW: I ordered BHR's midpipe about a week and a half ago... Catless, so I will update this thread when I get it, and tell you my first impressions (Do I even have to, we all know BHR's midpipe is the shit). I know Im not going to pass emissions because im premixing w/ Idemitsu and I have the Cobb AP>>> lots of oil and backfiring should be pretty easy, let alone to shoot some flames.

So if you shoot some flames and burn out the tailpipe sniffer... is that a pass? :lol:

Haha thats a good idea Wulf... lol I know I would fail but no worries because I have friends that can pass me so:smoker:

Yea I really doubt it'll pass in Cali. Won't even pass the visual without a CARB sticker. So make sure you steal a sticker. :lol:

Another thing to consider is if it's posible to get the same gains with Cobb + MazdaManiac tunning with the cat as without it (or if the tuning will melt the cat).

I'm installing my bhr midpipe without the cat this morning. I'll post some results when im done, and maybe a video of how it sounds with the exoticspeed r1-t :aroused:

Gotta take of one thing, will you run a custom map ? Cause "cats" can't support the same settings than catless midpipes and this can result in a power restriction in the end.

If you run with a stock map, then you'd better go for the sport cat, i'm not addicted to catless pipes running stock, the results can be really surprising, disapointing even some times, yeah flames and sound are cool, but is that what we care the most ? :/


Omg sorry, my english is getting worse each day... :/

:dunno: I like flames and sound :D:

I'm interested in this post as well

I didnt think most states still did the sniffer test? I know when I go get my emissions done all they do is hook up to the obd2 port and read for any codes and then pop open the hood and make sure there's an engine in there(thats why the guy said he had to check, lol).

I believe it goes by what county you are in... I could be wrong though...