A sterndrive or inboard/outboard drive (I/O) is a form of marine propulsion which combines inboard power with outboard drive. The engine sits just forward of the transom while the drive unit (outdrive or drive leg) lies outside the hull.Click to see full answer. Moreover, which is better IO or outboard?Inboard/outboards are just “marinized” automobile engines stuck in a boat. Outboards provide more room in the boat because they are installed on the transom, outside the boat. Four-stroke outboards offer much better fuel economy, less GPH, more MPG than I/O motors. Outboards offer better power to weight ratio.Furthermore, how does an inboard motor work? An inboard is a four-stroke automotive engine adapted for marine use. Inboard engines are mounted inside the hull’s midsection or in front of the transom. The engine turns a drive shaft that runs through the bottom of the hull and is attached to a propeller at the other end. One may also ask, what is the difference between inboard and outboard motors? An inboard motor is in side the boat, low in the bilge, permanently mounted, and drives a prop shaft which penetrates the hull. An outboard motor is hung on the transom secured with clamps. The out board contains the shaft and prop together with the motor in a self contained unit.What are the advantages of an inboard motor? Advantages of Inboard Engines Inboard engines are favorites for water sports like wakeboarding and waterskiing, especially with multiple skiers, as they have better wake control, major towing power and a clear transom for tow ropes. A lower center of gravity also helps to cut through heavy ocean waves.