We present preliminary results from the updated dynamical core of GEM-Mars, which includes the option of a new horizontal discretization. In the Yin-Yang configuration, the domain is decomposed into two limited area sub-domains with an overlapping region. This eliminates any problems with the convergence of meridians at the poles and improves the computational load balance in message-passing interfaces. We examine the impact of this new configuration on model results, in particular, in the polar regions of Mars.