The formation of complex craters requires some form of transient weakening of target rocks.Acoustic fluidization is one proposed mechanism applied in many numerical simulations of large craterformation. In a companion paper, we describe implementing the Melosh model of acoustic fluidization in theiSALE shock physics code. Here, we explore the effect of Melosh model parameters on crater collapse anddetermine the range of parameters that reproduce observed crater depth‐to‐diameter trends on the Earth andMoon. Target viscosity in the Melosh model is proportional to the vibrational wavelength, λ, and thelongevity of acoustic vibrations is ∝ λQ (Q—quality factor). Our simulations show that λ affects the size ofthe fluidized region, its fluidity, and the magnitude of the vibrations, producing a variety of crater collapsestyles. The size of the fluidized region is strongly affected by the Q. The regeneration factor, e, controls theamount of (re)generated acoustic energy and its localization. We find that a decrease in e leads to less cratercollapse and that there are trade‐offs between e and Q. This trade‐off contributes to the more realistic Qvalues than those used in the Block model. The diffusion of vibrations in regions with high stress and strain iscontrolled by the scattering term, ξ. Compared to the Block model, the Melosh model results in a shallowerzone of weakening in complex craters and enhanced strain localization around the crater rim. The parameterset that produces best depth‐diameter trends is λ = 0.2 ×impactor radius, Q = 10–50, e = 0.025–0.1, andξ = 10–105 m2s.