IMCO Marine redesigns lower unit for high-horsepower drive.

If you’ve upgraded your boat’s engine to a horsepower output that’s more than a MerCruiser Bravo One drive can handle, but you don’t want to spend the money on the expensive Mercury Racing Dry Sump Six drive, IMCO’s SCX4 and SCX drives with an upgraded lower unit could be the answer. The drive is rated for 800 foot-pounds of torque, but unlike the Dry Sump Six, it doesn’t need a transmission. The IMCO drives are designed to be a direct bolt-on replacement for a Bravo One.

The “SCX4” designation is because the drive is 4 inches shorter than on a standard Bravo One, and the standard SCX comes standard 2 inches shorter. The redesign centers on a new skeg profile. On the new models, the skeg runs all the way forward to the nose of the torpedo. It extends down and aft about 2½ inches to the primary skeg.

“The benefit of that leading skeg is that it allows the lower unit to settle better in the water,” said Fred Inman Jr., vice-president of IMCO Marine. “It pre-pierces the water to take pressure off the lower unit so it doesn’t want to ride up. It keeps the drive from wanting to lift.” The SCX4 is a popular Bravo One upgrade on catamarans running big horsepower, while the SCX is preferred for V-bottoms.

The SCX has been around since 2009, and the redesign came about as a result of some of the changes that custom or blueprinting shops have been making. IMCO will blueprint a drive for customers, removing minor flaws and perfecting the surfaces for an extra cost of $800. The IMCO SCX retails for $16,183. If you just want to upgrade the lower unit on your drive with the redesigned units, it will cost you $6,116.