I have a 1966 sears jon boat v bottom aluminum. 1985 4hp evinrude outboard. Transom measures a little more than 15 inches. Which tells me its a short transom. Motor measures 17 inches from ventilation plate to top of mount. Which tells me its a short shaft. Heres the dilema...boat doesnt steer good and seems like it has drag. Wont plane out. Im 140 lbs. The ventilation plate is 2inches below transom. Will raising motor up help at all. Any advice will be helpful. Am planning on building a jack plate out of 1/4 inch 3x3 aluminum angle. Motor torques up good in trash can of water.or should i get a 9hp and forget it. I really like my 4hp its light ez to store in garage.

Moving the motor up is not going to change the performance for that motor, you just need more horsepower. A 9.9hp or 15hp would do the job.