If you put on a dp, you eliminate the pre-cat. Will you sill pass emisions?

I don't want to put a dp on and then take it off just to pass emissions.

 

before everyone tells you too search...you're fine... it's when you remove the main cat that you start having emission issues

 

You need a well working air-pump, and main cat to pass emissions. If you are really worried about it, you can always buy products to put in your tank to help you pass, but you should be fine, assuming the other two I listed are in well working order.

 

I just passed with almost zero emissions and a downpipe. Just make sure the main converter is fully warmed up.

 

Are you using the stock cat or a high flow cat?

 

You should be able to pass the "sniff" test with a downpipe. Be sure you go to a shop where the smog tech isn't too picky. Some states require that you pass a visual test, where the mechanic is supposed to check to see that all of the smog equipment is on the car, including the pre cat. Many mechanics don't check. Some do.