Hey, I replied to your comment in the "Any Advice Thread".
Suboxone & Subutex are basically the same thing, except Suboxone has naloxone in it.
But the main ingredient is buprenorphine. It is buprenorphine that gives you withdrawals from other opioids, not naloxone.
Naloxones binding affinity is not strong enough to displace buprenorphine.
And even if it were, it would only stay bound for an hour at most. So it would not interfere with something taken later in the day.
Did you feel any euphoria from the Suboxone? Cause chances are, if you didn't feel it from Suboxone, you won't feel it from Subutex either. Especially if you're already at a high dose like 8mgs of Suboxone.