cumminallover

ok i was wanting to do an exhaust.. i was worried about the 2 o2 sensors... i was wandering if i take the cat out would it make it run better or do i need it in... i was wanting to take the cat out and put a 2 1/2 pipe frome the header flange to a magflow muffler then over the axle to a stainless tip.... any help would be appreciated.....

cumminallover

bump bump

taythegibs

cats required by law, your xj wont run well without it, itll make it louder but with the downstream o2 sensor itll mess up your air fuel ratio.

MWildmann

If you lose the cat and just put bungs in for the O2 sensors, you'll have a permanent CEL, which will mean it'll be permanently in "limp home mode" and fuel economy will suck. I highly doubt it will run any better. A replacement cat from magnaflow is only like $100. Keep it and do it the right way...

Metmknice

IF you use it for off-road purposes only, vatozone has a cat-delete pipe with flange.
Otherwise, confirm your cat is good/bad, replace if necessary. Performance-curve.com has a magnaflow cat back for 100$

cumminallover

ok so buy a magfow cat and do a stainless header and magfow muffler.. it will open it up performance wise and get better mpg?

cumminallover

i love the quitness so i dont want loud i just want her to breath better and get better mpg

MWildmann

Better performance=more noise. Generally a free flowing exhaust doesn't really give fuel economy gains unless there is something pretty seriously wrong with the system currently on there.

cumminallover

thanks alot