The discussion centers on the feasibility of using a 2-stage centrifugal pump with a 7.5hp motor for boat propulsion by restricting the output to a 2-inch nozzle. Participants emphasize the importance of understanding the pump's performance curve, as the stated flow rate of 100m³/hr likely represents maximum ratings rather than a single operational point. Concerns about cavitation and pump efficiency arise when flow is restricted, with suggestions that the pump is primarily designed for water movement rather than propulsion. The need for specific pump data and testing is highlighted to determine if the desired velocity can be achieved without damaging the pump. Overall, the conversation underscores the complexities of adapting a centrifugal pump for marine use and the necessity of thorough research before proceeding.