Previous three dimensional magnetohydrodynamic studies of the Large Helical Device are extended to include free-boundary calculations of two realistic equilibrium sequences. The use of an external vertical field to centre the configuration as the plasma pressure increases is shown to give results that are almost identical with the earlier fixed-boundary computations. The expected response of a set of magnetic diagnostic loops is calculated and the sensitivity of the Mercier stability to the treatment of resonances in the parallel current is also considered