If you couldn't find an answer, you didn't look very hard. It addresses this exact issue on the front page of the suboxone mega thread.. Since you were taking a large dose (8mg) a day for a couple weeks, you have a substantial amount of buprenorphine built up in your system.
After stopping suboxone, you don't have to wait at all to take other full agonist opioids. The effects will just be diminished until the bupe gets off of your receptors. The time it'll take for you to be able feel full effects is subjective, but in my experience, when coming off of suboxone, I would feel heroin after a day, but needed to do more. It was about 5 days or so before I could achieve full effects.
This is redundant and has been covered in multiple threads and is answered. Please use teh search engine for very basic stuff like this, it has been answered, believe me.
Closed.