Hi Mark. You can ALWAYS increase the diameter of your discharge hose without losing any pump performance, so to answer your question, yes you can. Just please be aware that this pump will NOT pump any higher than 7 feet vertically and setting it up for that total 7 foot head lift will max out the performance and power of that pump. This could result in a shorter than normal pump life. In other words, if your application requires a total 7 foot vertical head lift, I would suggest a pump that has a higher head rating.