If you want your team starting before Clan Boss, All Champions: 191-209
If you want your team starting after Clan Boss, All Champions: 171-189
These two ranges work with each other for UNM. These speeds can work well in Nightmare as well, but the closer you are to the speed of the Clan Boss the better. Differences of about 20 points or so of the CB speed can result in lapping of the boss (or yourself) and alterations of the turn order.
When mixing these speeds, on Ultra-Nightmare, they are roughly equivalent to the speed with a 20 points difference. Between the two the higher one will go first. So 191 will go before 171, but both will go after 172 and higher. The same concept applies to Nightmare, though the speeds required are lower and generally revolve around the speed of the Nightmare Clan Boss (170)