Can I put .11's on a full size flattop?

[ProfessorGAC]

4. What TP Said

Different string compositions have different densities, so the amount of tension required rises or falls for any given gauge.

I'd try the 11's though. Worst case is you loosen them and adjust the truss rod a little, or you can even "zero fret" at the net with a D string.

Wouldn't want to do that permanently, but might help prevent buzz without messing with the neck until you get a gauge that suits the current set up.