PISDYN is an advanced three-dimensional simulation package for predicting the dynamics of the piston and connecting rod assembly - enabling the optimization of the piston geometry and minimizing the need for expensive and difficult testing. Based around an advanced lubrication model for simulating the interface between the piston and liner, the engineer can use a hierarchy of structural models to minimize scuffing, wear, friction loss and piston slap. RINGPAK is an advanced two-dimensional simulation package for predicting ring pack dynamics, lubrication and gas flow for optimization of the ring pack. Based around advanced lubrication, gas and ring dynamic models, the engineer is able to reduce friction, wear, blowby and oil consumption, minimizing the need for expensive and difficult testing.