Since I added the Permatrim and raised the motor at the same time, I can't say with any degree of certainty that raising the engine or the Permatrim caused all of the positive results. I was trying to correct a porposing issue mostly. I endeded up with a boat with quicker and flatter planing, slower planing speed, no porposing and no more wandering at slow speeds. The last one was a surprise. I had intended to raise the motor and test then the Permatrim and test but due to time restraints I was not able to do it. This issue comes up so much on here that I really wish I could have done the seperate test so that I could have shared it with all. At the end of the day, the Permatrim is designed to run basically on top of the water, so raising the motor for achieving this position for me was needed anyway. if I had to guess which of the 2 things made the biggest difference, I would say it was the Permatrim. As far as set up goes though, by the book your AV Plate should be riding with it visible with water splashing over the top and not 2" or so under the water. I have the F225 which adds more weight to the stern so you may not have the porposing issues I had? Either way, the $150 or so I spent on the Permatrim was the best $ I spent on my boat so far. Good luck with yours.