I appreciate that research! Do you have any suggestions or advice as to where to go to find a good set of High flow cats? I would like to go with teh ARK R-Spec 6-2-1 headers BUT they don't have the high flow cat.

if you know of or hear of naything regarding how to set this up so that I can get some headers while still passing the emissions test I would greatly appreciate it!

Thanks again!

 

I suggest getting the ARK headers (since you want them) and a single high flow cat downstream of where the headers come together. If you look at the pictures on ARK's website you can see that it comes with a straight section of pipe with flanges. That is where you would get the cat installed. It appears to come with oxygen sensor spacers to fool the O2 sensors into thinking there is a cat in place. At that point the only reason to run a cat is for the sniffer test.

 

i installed DC sports headers on my brothers 2003, in my driveway. it did not have a cat for a day, until we were able to bring it down and have one put in. i dont remember having a CEL before the cat went in, it was like 6 years ago...sorry. also, dont worry about a high flow cat unless you are force induced with turbo, supercharger, or nitrous. unless you really want one, but your going to pay more for a Carsound Cat... much more! just go with one that the shop recommends for a 2.7 liter v6 and you should be good to go to pass the sniff test ! take it from me, i used to work in a muffler shop !







i think you can see by this pic of the front header that the sensor you see there is the second one in line... i think... i just cant remember right now. i will ask my brother later if we extended the wires to put both second o2s behind the cat... i dont remember doing all that, so i think all 4 sensors were in front of the cat.









also, having a cat is good for the earth. dont be a dick to the earth... or it will be a dick back to you

 

You can't have had all your oxygen sensors before the converter or it would have thrown a CEL unless something else is broken.

 

i know... i cant remember if we extended the wires and put the o2s behind the cat.... im saying we must have... but... its been so long.

 

Thank you all for the info! Very helpful as always!