Mercury Racing’s Supercharged V8 Outboard Motor Makes 500 HP and Whines Like Crazy

If you’re not big into boating, you might think of outboard motors as weedy, sputtering engines lumped on the back of tiny fishing dinghies. In reality, they’re just as often horsepower monsters charged with shifting big boats at a rapid pace. Mercury is in the business of big outboard muscle, and its latest supercharged rig demonstrates that ably.

The new Mercury Racing V8 500R is named like a muscle car, and outputs 500 horsepower to match its moniker. The 4.6-liter V8 attains this figure with the aid of a bespoke Mercury supercharger, which provides a serious power boost as well as the characteristic whine of pulley-fed forced induction. It’s built to run on 89-octane (95 RON) fuel, a touch higher than usual for an outboard to help cope with the boost.