So I have the code p0420 and I was wondering what aftermarket cat you guys would recommend. I don't want to spend 1100 for an OEM cat so any help full tips will be appreciated. I also don't want a mid pipe because I don't want my check engine light eliminated unless if you guys know of one that doesn't. Thank you for your time

 

There is one hiflite has been using that was ~$100 and he says it has not failed him yet, search for some posts by him.

 

Thank you I think I'm going to go with the rp super cat.

 

Where do you live? If you have the sniffer emission test then some(maybe all?) people have failed with the rp supercat. You should still take a look at what I suggested earlier as it is very cheap and apparently works very well according to the guy.

 

I live in north Carolina. There website claims there new design phases the sniffer test with flying colors

 

i've discovered if there is a sniffer test, a bad stock cat can fail out the tailpipe, but still pass the OBD monitors, so it'll fail smog, but no CEL...

 

It will probably pass but just know it has said "Because this is a new design, CARB and Federal emissions certificate is pending. This is a perfectly street-able cat system but is for off-road use only" since at least 2005. So it is probably not a new design still and I guess they never got federal or CARB certs or they would probably update that.

 

I searched HiFlite and I think he's been using a universal magnaflow cat. I want to avoid using universal cats but what do you guys think of the walker or maganaflow exact fit cats that are from autozone they come with a 5 year warranty?

 

get a Cobb, I have no cat just OBX mid pipe and eliminated the 420 dtc hasn't let me down yet, but i also i live in Md so our emissions test is different then yours im assuming

 

The only cheap universal that I know of that someone has good things to say about is the one hiflite999 is using. Pretty much all other cheap universals will get killed by the rotary, this one may as well but so far he says his is in great shape. You could PM him and ask him what the product number is that may be easier if you go that route.

 

What accessport do you have? Or what access port would you recommended?

 

MazdaManiac HOME

Either buy it there with or without the tuning or buy a used one from somebody. I believe MazdaManiac is the only one that sells new ones for the rx8.

 

You are correct Manic is the only one that sells Cobbs for the RX8.

@cesarthepleaser it will be cheaper to obviously to purchase one off another member here that will have all the tunes on it, or you can pay the extra $$ and get it str8 from Manic and what ever services he offers. IDK what all is included as far as tunes if you choose Manic, I got mine off a member here a yr 1/2 ago.

 

OK thanks a lot I'll check it out. Are they easy to install and how exactly to you delete that code with the access port? Oh and also Is it true when you put a mid pipe you smell like gas?

 

Cobb only mask CEL, without proper cat, you'll gonna fail sniffer test no matter what.

 

I was only putting it out there as a possible solution depending on how his state does emissions testing, here in MD they don't do the sniffer test.

 

Plug and play basically until you want to do something like Mask a cell (see below).
Smell? Well that's a personal and relative but generally speaking ... yes it's really really really stinky. Any of my friends or neighbours that get stuck behind me complain.
Personally I like it .. reminds me of my 2 stroke snowmobile.

I'm not trying to split hairs but the Cobb doesn't actually do this.
I know you know this Shinka but many of us tend to over simplify Cobb Access Port.

So @ cesarth

The person needs to download Access Tuner Race software and modify their own Map and upload it to the ECU via the Cobb Access Port.

It's a common mistake made by many on this forum that the Cobb can do all these wonderful things like RPM limit and Radiator fan turn on temps.
But the physical device you will receive (the Cobb Access port) can not do any of these things.
What does do is allow you to upload a new ECU map. Its this map that you make these types of changes like rpm, rad fan, mask a cell.

This is done with software that doesn't come with the Cobb AP ... it's called Access Tuner Race.

To get a copy you need to fill out a form from Cobb (on their website) to download the software for free however you can't do this until you have a Cobb AP as it requires the S/N for the AP unit.