In the first part of this series, we discussed the impressive output of the new LS7. Let's now see how it makes all that power. Let's look at the lower end first, since it's the foundation of any long-lasting engine. Minimal reciprocating weight and high strength are goals for any high-performance engine builder, and these things were obviously on the minds of the LS7 engineers. A forged crank isn't unheard of in production engines (the famed Ford 5.0 got one), but it's welcome here for its added strength and slightly decreased weight. Titanium rods are truly rare among production vehicles, and this is the first use of them in a GM engine. The cast hypereutectic pistons, likely used because they're lighter than forged pistons (they's also more fragile, so nitrous junkies beware!) are treated to an application of anti-friction coating and use full-floating wristpins. Most exotic might be the dry-sump oiling system that employs pressure and scavenge pumps driven from the front of the crankshaft.

Whereas a typical wet-sump system simply pressurizes the oil galleries and depends on gravity to drain the oil back down to the pan for collection by the pump pickup, a dry-sump system uses an external reservoir and actively collects (scavenges) oil from areas such as the lifter valley and heads, where pooling often occurs during high-RPM and high-G operation. Such a system is far more complicated than that typically employed on production vehicles, but also is well suited to the Z06?s mission profile.

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