hey as some of you know i did a serious build on my hemi but i still have a issue my exhaust is this order- pc long tube headers with first set of o2 sensors then 3 inch cutouts then adaptors from 3 inch to stock size then 2nd set of o2 sensors that are on spark plug non foulers then stock y pipe but some pipe removed for fitment then were stock muffler was is a 1 in dual out flowmaster. so as you can see there is no catalytic converters i had to cut them for the long tubes but when you cut them out you dont want to reuse them due to flakes of metal can clog it up so as predicted engine light came on after 100 miles and is running lean so would takeing off non foulers work. and yes high flow cats is a option jus not right now so if there is any thing i can do to fix this problem i also have a sct tuner could that do any thing?

 

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High flow cats don't outperform the stock cats hardly at all, not worth the $$.
If the 1st O2 sensor is hooked up before the cat like stock, it should run normally even if the 2nd sensor isn't behind a cat. (The 2nd is just there to check if the cat's working, it doesn't affect the mixture if it shows a CEL)

I've heard of some people putting steel wool in the non-foulers to remove a CEL as well. Good luck

 

I had a hard time following your post...fyi, but I read it a few times and thinkI unerstand?
As stated, even oem cats are high flow so yournot losing any peformance really. My mustang dynoed only 4rwhp less at 496rwhp, so a 250ishrwhp vehicle isn't losing more than 2 or 3hp topps. I would get some cats in there.
Cutting the cats off and re-welding them in is perfectly fine as long a you file off the internal burrs first.

 

Are getting a code on the post cat that says its running lean after doing nonfoulers cuz that is exactly what i am experiencing on mine right now