in washington to pass emissions the obd2 monitors have to be ready and u have to pass a gas cap test and u cant have any codes in the comp. but taking out the cats and reinstalling the down stream o2 sensor will set a code
for cat effiency below threash hold so how would u get around this with installing headers.

 

Either get an O2 sim from here www.o2simulator.com or extend the O2 sensors and weld em in on the b-pipe after the main cat.

 

Thanks thats all I needed to know. Now I know what to get and it's cheap too