The white smoke coming out is the dissolved carbon burning off, not the Seafoam. In the new or low mileage engine, you won't see that much white smoke. Sea Foam actually helps to clean the catalytic elements, restoring its efficiency, and reducing the "rotten egg" odor you occasionally smell from some catalytic converters.
I have tried this task as video showing and never have had catalytic converter failure so far. I don't think you need to disconnect the catalytic converter at all. So many people in the world using Seafoam now. Yyu can search on YouTube for "Seafoam" and will see a lot of videos for this seafoam smoke.
Last edited by Ricardo567; 01-26-2013 at 02:49 PM.