I recently bought a 1979 18 ft sea star tri-hull. The boat came with a 200 hp Evinrude 2 stroke outboard on it (1980 I believe). I know that this is far too much engine for this boat and I plan on changing it out soon. but for now I'm having issues with stability. When ever I get up to about quarter throttle the boat starts hopping, even when in dead flat water. The engine has stabilizer fins on it and they are kicking quite a bit of water up in the back. If anyone has any suggestions on how to prevent the hopping from happening I would appreciate it. I'm nervous she might flip over if I push it too far. Not sure if this is just a problem with the tri-hull design or something else. Also on a side note the boat came with jack plates that I have not installed yet to raise the engine up a bit, not sure if this will help or not.