  We numerically simulate gravitational shock wave collisions in a holographic
model dual to a non-conformal four-dimensional gauge theory. We find two novel
effects associated to the non-zero bulk viscosity of the resulting plasma.
First, the hydrodynamization time increases. Second, if the bulk viscosity is
large enough then the plasma becomes well described by hydrodynamics before the
energy density and the average pressure begin to obey the equilibrium equation
of state. We discuss implications for the quark-gluon plasma created in heavy
ion collision experiments.
