  Colliding wind binaries (CWBs) are unique laboratories for X-ray
astrophysics. The massive stars in these systems possess powerful stellar winds
with speeds up to $\sim$3000 km s$^{-1}$, and their collision leads to hot
plasma (up to $\sim10^8$K) that emit thermal X-rays (up to $\sim$10 keV). Many
X-ray telescopes have observed CWBs, including Suzaku, and our work aims to
model these X-ray observations. We use 3D smoothed particle hydrodynamics (SPH)
to model the wind-wind interaction, and then perform 3D radiative transfer to
compute the emergent X-ray flux, which is folded through X-ray telescopes'
response functions to compare directly with observations. In these proceedings,
we present our models of Suzaku observations of the multi-year-period, highly
eccentric systems $\eta$ Carinae and WR 140. The models reproduce the
observations well away from periastron passage, but only $\eta$ Carinae's X-ray
spectrum is reproduced at periastron; the WR 140 model produces too much flux
during this more complicated phase.
