i have a v6 tiburon with headers, the stock headers had 3 cats all together, the main cat and two pre cats. Now with aftermarket i only have one high flow cat. will this pass here in ny due to losing 2 of the 3 cats, or do you only need one cat in ny? thanks
as long as its not throwing codes it should past. I doubt any tech doing the inspection will know its suppose to have 3 cats so if they see one they will be happy. If they even look for it.
well technicallyin NY you can do anything you want to your exhaust as long as it retains the same equipment as oem, meaning yeah you would need all three cats to pass, however, if you pass the OBDII code-reader test you will be fine…go to autozone and have them run you for trouble codes, if you dont run any, your fine
alright thanks will do.
the first 2 cats are only for start up until the main cat heats up after the car is warm they are pointless…but to answer ur ? u should be fine as long as the o2 sensors for those missing cats arent throwing codes…which they usually dont if u take those cats off because they are heated O2 sensors and dont read anythign until they heat up and by that time those cats do nothing anyway
i took off 1 of my 2 cats, the pre-cat on my factory exhaust manifold is long gone being replaced with a header. my ecu was then throwing a code, so i wired in an 02 sensor simulator, the ecu reads that fine, the code went away and my car passed inspection in june just fine
I passed with no cats 
As long as you don’t have any codes being thrown, you’ll be fine. Unless the inspector is a PITA and does a visual, and knows exactly how many cats should be there.
Like everyone else said, as long as your ecu isnt throwing CELs you will 99% be fine unless the place you go does the visual inspection. Also depending on your location in NY you may have to pass a sniffer (downstate).