I have a 15.5 foot alumacraft semi v jon. I have a Mercury 4stroke 9.9 on the back. It will push it about 12-13 mph with two people and gear. My question is will a whale tail help it get on plane? It never seems to get out of the water enough to feel like I am on plane. I adjust weight forward and backward till the motor sounds like it is running effeciently. I cannot afford a bigger motor. My buddy can make me an aluminum tail for it but not sure if it is worth the effort. I welcome any advise. Thanks!