ok im gonna change the prop on my boat its a 17.5 bass tracker with a 45 hp merc,its very slow to get on plane.to speed is about 25mph,but rpms is about 5000.so heres my question it has a 10 3/8 x13 p should i go to a 11 pitch or 15 pitch?im trying to get it to 5500 rpms and want it to take off...