so i stripped the bung for the o2 sensor on the stock one. got a chikara, the $100 one. id have more respect for it if it wasnt painted. anyhow, no cats 2" off header. my intake used to be the loudest part. now the exhaust is untill 4K... after 4K its dead ******* silent yet it accelerates nicely. chikara is a decent header for the money. lighter and flows better than stock. i just feel like a momo for having one =P