Can I install a OBX header and use the stock Cat or a high flow cat in california? IE, smog legal? I’m trying to figure out a way to get an aftermarket header to get in my car that would be California legal.

 

As long as you use the stock cat you should be fine. I recently put this combo on my car. There are no codes and no check engine light.

 

Most likely not. Everything that flows air between the intake filter and the cat must have a CARB number to be legal. So anything after the cat doesn't need the number (eg. cat-back exhaust). Of course depending on how it looks the smog tech may not notice it and you will pass anyway. Or there are also tech who don't care as long as it still has a cat...

 

Are there any known issues with the OBX header that I need to look out for now? I know back in the day there were?

 

Mine was fine. Some had problems with the ports not matching up or the bolt holes not lining up. the only other drawback to it is the lack of a flex pipe.

 

So you would definitely put the stock cat on, and get a flex pipe?

 

I am running mine without a Cat, but the shop that did the work, has done plenty with the OEM cat, with great success.

I would tell you just order the Header have the flanges made for the OEM cat and you will be fine, it will take a VERY trained eye to see that the factory exhaust manifold has been changed.

As to flex pipe, I did not use one I used the OBX provided swivel/flange so far so good!

 

Be sure to talk to folks in CA....
Your rules are very different...
Sure....we do have tests....
But if it is "clean" we can run any cat, any maker, in any configuration...
In CA....it must be "approved"....and you have a visiual and a "sniffer" test...
In most other states...sure they look...but no approval checks...then the car gets plugged in to the odb2 to check for readiness and then sometimes a dyno with a sniffer.....
Many stories of folks in Ca returning their car to "stock" yearly/bi-yearly for the tests...have frankly NEVER heard of that outside of CA except in extreme cases....
Generally we have no light, you pass......

 

So should I have this done at a exhaust shop or someone who specializes in installing mini stuff.

Get the obx, felpro header gasket, and use the stock cat?

 

I'm in ca, and even with the stock cat it is not legal. I have had the smog tech look under the car and check. I have a rmw header but I swap it out for smog checks. Last year I removed thee header, had it smogged and reinstalled the rmw in 3 hours total. My advice is get a good header and swap it out when smog time comes, it's easy and makes a good power increase.

 

Use the factory gasket, and pretty much anyone that is competent to do the work can do it.

If you have a good MINI shop that has welding experience then let them do it all at the same time.

Install Header
Make Cat section
weld it all up

 

Wow I've never had a smog tech look under the car. Even on my mustang maybe because both are lowered.

I would like to avoid having to remove it all the time honestly. One reason I was wondering if I could install the magnaflow high flow cat that is cal legal

 

Even with the magnaflow cat I would say not legal. But it's only every 2 years. And my mini is lowered and they still looked, but it depends shop to shop on how detailed the check is.

 

Here in Florida Years ago when we did have inspections, (a failed process), I actually worked at one of the facilities.

We had a mirror to look for the Cat on cars as we were to verify that it was there, I am sure that CA has the same rule/process, but in an effort to make things go quick, if the thing passes with clean numbers and does not sound like a Drag Car, no one looks!

Luckily we no longer have that crap and I can run w/o a cat!

Funny side note; back then I had a Honda with dual Mikuni 2 barrel Side Drafts (fuel injection was completely removed), and running right it would still pass even though there was no cat and a Tri-Y Header running into a SuperTrap Muffler.

You wanna see funny, watch the morons that work there try to put the sniffer in a SuperTrap Muffler!

 

With the stock cat it shouldn't matter. No extra pollution is being created

 

Rolling on the Floor Laughing!!!!

 

Running the stock cat is your best bet at passing smog test. The swivel joint that comes with it seems to be ok but a flex joint probably would be better. If you have a shop that doesn't really check under the car then you're probably good.

 

The shop I would have install it said they wouldn't do it because it wouldn't be legal in CA. Guessing I'll have to do it myself. You just take it down to the local muffler shop and have it welded? Where did you get the flex joint from, and is there some place I could get an extra stock cat from for cheap?

 

If only California was that logical.....
With most states....
No light means you pass...
If you are in a state with a "sniffer" test....exausts tests ok...you pass...
But like I stated before....
CALIFORNIA is different....
While 90% of techs can't spot an aftermarket pulley (especially if painted black..hint)...90% of techs can spot an header....same for a CAI (sure on a car with carbs it might have made a difference, but with modern fuel injection...nope...but state regulations are 20 years behind)...get a used jcw or other one with a sticker...do what you can to "look" stock...
Imo....unless you want to make lots of work reverting to stock...
I would do a CAM.....injectors, custom tune... Car would still look stock...
Good luck...I can say I tried.

 

I run the OBX header with a Random Technology Cat with both a pre and post cat o2 sensor. No check engine lights and it should pass smog but we dont have that here in NC just has to pass visual inspection and have no OBD codes. It's a pretty good setup and the RT cat is less restrictive than OEM and cheaper. The joint that comes with it is fine but I would recommend that you do a lower powerflex engine mount and and/or a better upper mount to minimize stress on the joint due to engine movement. I run a vibratechnics upper mount and love it.

 

Smog coming up...

Were you able to pass smog using the obx header and an aftermarket cat? Or did you have the stock cat welded? Also, sorry for digging up an old thread.

Thank you,