I was doing a search for Cats for the MINI and found this "Poor Man's Header" used for MINI Challenge in New Zealand. Interesting though is the reason they state it should be done, "Reason:To eliminate the risk of engine damage caused by catalytic converter failure."
Has anybody tried this see here below?

http://www.motorsport.org.nz/Pdf/0809 Champ Amdmt MC-09-T004.pdf

 

I know of a few guys who have kept the standard manifold but cut out the pre cat and weld in a straight piece of pipe as this makes the standard manifold less restrictive. Don't know what type of gains you will see but you should see something as the precat is the most restrictive part.

 

cool but read it again . looks like they eliminating both pre and cat but must maintain shape of pre .externally . cat can be cut out and straight pipe in it's place .

 

But they remove the innards or guts off the Cat as well, right?
Just reweld the exterior of cat to look OE.
OK, I carefully re-read and understand.

 

This is really only a valid mod if you are running it off road. The minor HP gain is not worth all the horrible gasses you would be pumping out into the air we all have to breathe.

 

Hell yeah!!! We Mini drivers are all hippies at heart...

 

poor man's header is OBX .

For the work involved on the stock manifold, I'd pick up an OBX header (199.00) and just graft on the stock cat. Many have done this mod and seen hp/tq gains, no code issues and you remain green.



ps - lots of threads on this

 

cars in usa account for something rediculously low in the world scheme on emissions 5 percent of a percent or something silly low like that . you'd be better off talking to north korea about their missile launches .... there's a few thousand minis for every launch i'm sure .

 

Well, it's not so much about pollution percentages for me. It's more about good citizenship and being polite. I just think that running sans cat on the street is a pretty ****** thing to do. Kinda like sitting next to me in a restaurant and blowing cigarette smoke on me and my kid. It's just not cool.

 

Very true...I don't see how the car runs at all with the pre-cat.
I removed my pre-cat and replaced it with a not-exactly-straight pipe, it definitely makes a difference.
My main cat is still in tact and functioning normally.

One other thing...my tail pipes are not even close to being as black on the inside as they used to be with the pre-cat installed.

 

Im installing my oem header back in the car with the pr cat removed. We will see I guess.

 

Can someone help me put the the picture up for Reference Article 13.2 below:
http://www.motorsport.org.nz/Pdf/0809 Champ Amdmt MC-09-T004.pdf

BTW: I'm not gonna do this (I think), just really curious if anybody has done it, what it sounds like, and what they butt dyno read. I added granola in my cat, soy into my resonator, and wheat germ/thc combo in my mufflers. JK

 

If this isn’t required to make spec in a racing series I think gutting is a lot of work. Just replace the pre-cat; there’s no percentage in gutting the main cat.

 

tru dat . and since everything today is global this an that ,it's not cool what china does to our atmosphere either . but greenies need someone to beat up so hotrodders are accessable so ..... seriously your lawnmower is waay killing your neahbors ,

 

From the Picture it looks like they did the opposite, cause it says they need to keep exterior as is of precat?? Looks like and staight pipe the cat.
I've been trying to get the picture up for like and hour and a half, I guess there is a lock against it or something.

 

Now thats not fair, at least they're supporting and trying to implement rules in the Montreal(Ozone) and Kyoto(Global Warming) Agreement.

Sorry but cant say the same for the US thou....

 

Got mine back on today. Over all the sound is a little louder but not much at all. No way to feela power gain but Im sure something had to happen. And my CEL is gone now that the cat is back on.

 

My take on all of this is, by removing or gutting just the pre-cat would increase "the risk of engine damage caused by catalytic converter failure".

 

One of the reason hot rodders get picked on is because they make up lame excuses for doing stuff like taking the cat off of street cars.

Just trying to do my part to bring some respectability to our passion…