I had a customer bring his boat to me to tune. We met at the launch and he was already in the water. We tried to get the boat on plane and the prop would break loose every time as soon as the nose started to break over. We tried 10 times to get it on plane. It was a new prop and he thought it was the problem. We put the boat back on the trailer so that I could see the prop. I noticed his drive shower pickup was less than 1/2" from the prop. He told me that he just installed it. I pulled it out and cut it right there at the launch. He told me that there was NO WAY that was stopping the boat from getting on plane. We put the boat back in and it promptly jumped on plane. The pickup was just to close to the prop and was disturbing the water so much that it caused the prop to cavitate when it needed to bite the most.
Eddie