What does it take to make your boat porpoise, and what is your set up, ie boat, motor and prop? What speed does it come on plane? jim
For clarification: Porpoise is the bow going up and down. If left in that condition, the porpoising will usually increase in intensity until down trim is introduced again or the speed of the boat is changed to accomodate the out-of-trim condition. Porpoising is usually a result of insufficient weight in the bow for a given trim position or mounting height of the engine. It can also result from an incorrect prop selection. Chine walking is a condition where the boat rocks from side to side on the chines - or, put another way, the boat rocks back and forth on its rear fenders. This condition also tends to become exaggerated if speed and/or trim is not immediately introduced to remove it, and it can result in a loss of directional control of the boat and ultimately even ejection of the occupants. Chine walking can result from weight distribution in the boat, hull design, engine set up, or trim position - or some combination. Whereas porpoising can happen even at low speeds, chine walking is almost always associated with higher boat speeds. If I've got this wrong I'm sure someone will straighten me out!
