will i or how do i pass emissions(i live in Illinois) with mac headers a high flow y pipe no cat and a 3" catback? Do u think i will pass with no mod to this setup or what can i do..thanks..btw i will be putting a 3" cutout as well right at the end of the y pipe today...

 

dunno about IL, but here in MASS no cat = fail emissions

 

Your not going to pass without a cat. What you should do is have a catless Y-pipe with a cutout to run most of the time, then a catted Y-pipe to put on when you go for emissions testing.

 

i only have 1 supercat right after the y pipe and i wanna fit the cutout right b4 the cat but there is no room

 

Buy someones stock catted y-pipe.

They go for next to nothing.

 

You can only pass with that setup if you have a '96+ (OBD II) car, where all they do is the PCM scanner test.