Timing Advance required?

If the timing was "good" to start with, the carb won't affect it, except that the characteristics of the throttle/ "ported vacuum" for the vacuum advance may and probably will be different than the original. Whether it's enough different to warrant any worry will simply require some experimentation.

What I mean by that is that the vacuum port may "come in" earlier or later, and may generate more or less vacuum at a certain throttle setting than the original carb. This of course will cause more/ less vacuum advance. It just might not matter much.