Two change management strategies: a minimum change, exploitation strategy (kaizen) and a maximum output, exploration strategy (kaikaku) have been applied in a manufacturing case study. Value stream mapping and discrete event simulation were used to analyse the production system changes, with regards to robustness and total lead-time, to increase knowledge of how to choose change management strategy. The results point out that available time is crucial. It is important to consider not only product specification and return of investment, but also the change and risk management. Future research should develop engineering change management further.