I recently purchased a 2005 Z20. I ran the boat once since purchase. When slowing down and coming off plane I get a huge backwash over the transom. I trimmed the motor all the way in (bow down) before decelerating. I slowed down at a consistent and comfortable rate. I am convinced if I came off plane any quicker I would have swamped the motor. I've had other boats but never a bass boat. Attached is a picture. The boat was repowered with a 4 stroke which I believe is heavier than the original 2 stroke. The boat has 4 batteries (75 lbs. each). Is this amount of backwash normal?