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Part 2: The engineers and technicians design and build and redesign and rebuild until they get it right.
By Capt. Ken Kreisler — June 2002
"Take a look at this," says Craig as I linger just a moment longer with the gravity-defying oil globs. The door to one of the dyno rooms is open, and he's hovering over an open manifold cover on a 1,000-hp 1050 SCi stern drive racing test engine, now shut down. I immediately see the springs we were watching. "We're also trying out a new, easy-off manifold cover," he says as he points over to a worktable near the skidded engine. "And we're playing with a new gasket. It's not there yet, but we'll keep testing until we get it just right."
That's the way it goes at Mercury Racing. The engineers and technicians design and build and redesign and rebuild until they get it right. "The Kiekhaefer drives developed here were a revolutionary jump in propulsion as far as horsepower capacity and torque were concerned," says Mackie, as an example.
Once the technology takes shape, it's off to Lake X, the St. Cloud, Florida, test site where the prototypes are run way beyond normal limits, all in preparation for the grueling and machine-killing racing circuit. Competitions like the 24 Hours at Rouen as well as the many APBA Offshore Racing events push the physical and mechanical boundaries of both man and machine.
"Many of the consumer products are a result of what we do here," says Mackie. For example, Mercury Racing's K-planes were originally designed for raceboats but are frequently purchased by owners of hard-running, high-performance consumer craft who want to stay on an even keel in less-than-ideal conditions at far-greater-than-normal speeds. Zero Effort controls were likewise developed for raceboat drivers who needed to frequently and rapidly change throttle settings when their boats suddenly went airborne, but consumers discovered they also provide a better sense of position and greater resistance to throttle creeping during aggressive driving. And specially formulated lubricants originally created to help an engine and drive live through tortuous racing conditions also impart a greater sense of security for owners who run their boats hard.
Then there are the engines: powerhouse outboards like the 200XS, 225XS, 250XS, and the awesome 300X; the 2.5EFI Offshore and 2.5 Drag; the Pro Max 25X. The performance stern drives include the Scorpion 377 and HP 500 and HP 575 SCis in addition to the aforementioned 525 and 1050 SCi engines.
Mackie points out several particular product developments as we walk the floor. The first is Mercury Racing's Integrated Transom System (ITS), designed to enhance drive height flexibility for stern drive engine packages with Bravo One XR drives. "Those XR gearcases, by the way, are CAD solid-modeled, CNC-machined units that feature a redesigned bolt-mounting flange for more strength and durability," says Mackie. He explains that due to the unit's longer torpedo, its "blowout speed"--a sudden and dramatic reduction in thrust when very low pressure cavitation bubbles forming along the drive reach the prop blades--is significantly higher than conventional designs.
According to Mercury Racing the ITS system has more strength and durability than any of its predecessors. Mackie cites such innovative features as the built-in seven-inch setback (for improved running attitudes), lengthened heavy-duty drive input shaft, integral hydraulic twin-ram power steering and electronic trim and tilt, and new drive cover (for added cooling). In addition, there is a rear drive cap with built-in tie-bar attachment and trim and steering rams that are multi mounted to the gimbal ring (to transfer the load back to the transom). "And that tie-bar attachment fixture that is built into the new rear drive cap helps make multiengine applications easy by eliminating the need to change drive caps," he adds.
This article originally appeared in the February 2003 issue of Power & Motoryacht magazine.