Hello, in themselves sponsons don't cause porpoising. please therefore provide more details of boat and motor eg boat weight and beam and transom deadrise. I am building a 12' twin sponson boat and here is the 1st of two of the sponsons to be welded up. it is made of 5053 aluminum and welding with 5356 filler.. Sponsons 04/25/10 sponsons on this boat are utilized to help stabilize the craft in choppy water or high wind conditions, or both. the unique sponsons described and.
