Internal coating of cylinders has always been a challenge for cars engineers. Driven for more than two decades now by the ecological and economical constrains applied to the automotive industry, it constitutes a dynamic way of research and development for industrial applications. One of the most economical processes for this kind of coatings is the rotating twin-wire arc spray (TWAS) system. Meanwhile the actual quality and the performances of the corresponding coatings still leave place for some improvements. Therefore, in the work presented here, attention was paid to the second atomization phenomena in a TWAS system considering the influence of the gas flow parameters on the particles’ morphology and deposition behavior. Numerical modeling of the plume and comparisons between several designs of the second atomizing units were also considered.