One of the design briefs for the C4 Corvette was that it had a minimal frontal cross-section, so it was less visible to radar. In other words, it helped you get away with speeding. Another target was to be the most powerful car sold in America. The 1990 - 1995 Corvette's ZR-1 option package was the most expensive in the history of Detroit, but it gave the Corvette world-beater firepower. Its LT5 V-8 was designed by Lotus and built by Mercury Marine, an all-aluminum, four-cam V-8 that was developed from the Lotus Etna concept engine, not a Small Block. It shared the traditional Small Block 4.40-inch bore spacing (after a quick redesign) and used an early form of passive Variable Valve Timing. The 32-valve V-8 breathed through 16 individual intake runners, half of which could be closed off at low loads. When opened, those runners breathed through valves that ran on a far more aggressive cam profile. This allowed the engine to be both torquey and efficient at low-rpms, but powerful at