Originally posted by v4lu3s
you may want to get an o2 sensor simulator as well since you will get a secondary o2 sensor check engine light with a test pipe. I recommend a carsound cat over a test pipe for an obd2 vehicle...
Im not trying to contest but why is carsound cat better? if i do get the testpipe, im planning to swap it with the stock cat everytime i do a smog check, since smog check is only once every 2 years in CA.