Originally Posted by HossMN
If I read your message right, the tag installed by Lund says 55 hp max. If you are in the US, you have to use that as your rule for the absolut max hp motor installed on the boat. The formula you mentioned is for the boat builder to derive that rating. Once the tag is installed, that is all you can use to determine how large of a motor is legal.
Yup. And I can tell you from my boating training during DNR-sponsored classes that if you operate a boat in Wisconsin with an engine larger than that listed on your plate, you will be ticketed. In fact, we were told as o part of those classes that years ago if you had a pair of engines (main plus kicker) that totaled together more than your max rating on the boat tag, the DNR was ticketing you. The courts put a stop to that practice. Now the main and kicker are considered separate power sources not to be added together.