I have been picking up various parts as I go along. What I have so far is the os2 housing and a 3" downpipe. My question is can I install these without the rest of the exhaust being 3". I know this is not the ultimate way to go, I just want to get these on the car. Will the DP bolt up to the stock cat.?

thx

 

most of the major exhaust manufactures allow their parts to fit with the stock cat.

 

You will be good. I guess you have to start somewhere.