Re: Porpoising
Parker1700;
The motor trim allows you to use the prop angle to lift the stern and thereby push the bow down. In other words you are using the prop to compensate for the boat balance (or imbalance). Obviously this is an improper use (and inefficient use) of the prop. However the boat manufacturers design the transom with an angle to allow this (negative) trim. In short they know the boat is not balance correctly.
The same manufacturer (and his dealers) will tell you that "our boats do not need trim tabs. So I can only deduce that this porpoising is (in their minds) something to enjoy or shall I say endure.
OK I am being a bit sarcastic, but the logic still holds true.
Install trim tabs and you will then be able to put the motor trim where it is most efficient and use the tabs to eliminate the porpoising. Using a Hydrofoil may help, however since this is the same as a fixed trim plate, at some point the amount of lift at the transom will be too much and other handling and efficiency issues will come up.