Today, untold zillions of molecules of iron, aluminum, and plastic composites awoke at the flick of a human wrist on an ignition key. They were compressed or stretched by the forces of combustion, they transferred heat from cylinder walls to coolant, they transformed vibrations into noise, and they were lubricated against the forces of friction. But before these molecules were crafted into modern engines, virtual facsimiles of them were subjected to vivid, lifelike simulations of these actions, the whole shebang conjured by an artificial intelligence as sophisticated as anything conceived of in The Matrix.
A year ago, the luckiest of these virtual alloy molecules were grooving and grinding to the synthesized machinations of the first V-16 engine of the millennium. The mission to build an actual running engine for the Detroit-show-stealing Cadillac Sixteen concept was launched in mid-March 2002. At that point, Cadillac could have simply FedEx'd a couple of V-8 crate motors to a prototyping shop and subjected them to a welding-torch wedding. That process could have produced a V-16 that would start, idle, and move the concept car onto and off its auto-show runway.
Instead, GM decided to flex its advanced engine-engineering muscle and highlight technology that would soon be appearing on the Gen IV Corvette V-8 by designing and building a real V-16 from scratch—one that could operate under load at redline on a dynamometer. No weld-'em-up motor could ever withstand that.
The engine's refinement and output were supposed to get folks thinking again of Cadillac as the Standard of the World. It's hard to beat a smooth-firing sixteen for refinement, and it's tough to top 1000 horsepower and 1000 pound-feet of torque. But the engine also had to achieve the fuel economy of a competitive V-12 while running on regular-grade fuel.
This daunting mission fell to Larry Cooper and about 10 people from the Powertrain High Performance Vehicle Group. They started with the basic architecture of the next-generation Corvette's V-8, including its variable cam timing—a first among pushrod engines—and a Displacement on Demand system that shuts down cylinders to save fuel under low-load conditions.
Calculations of the cylinder pressures required to hit the output targets suggested the need for a big bump in per-cylinder displacement, so the bore and stroke were both increased by 6mm relative to the current 5.7-liter V-8. Small-block cylinder walls don't have 6mm to spare, so adjacent cylinders ended up touching each other, and coolant could no longer flow in between the cylinders. This complicates the cooling system, sometimes causes the cylinders to go out of round as the engine heats up and cools down, and presents dozens of other problems that don't spring instantly to the human mind at the outset of such a project.
This is where the team engaged the General's considerable computer-engineering might by sending the basic engine design off to be thoroughly modeled, developed, and tested in the digital realm. In this cyberworld, the V-16 would be cold-started, overrevved, bogged down, blown up, and otherwise abused to the point of repeated destruction—all without ever staining a floor.
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