1990-1995 C4 Chevrolet Corvette ZR1: Engine and Features
The C4 Chevrolet Corvette ZR1 was first produced in 1990 and ended in 1995 after 6,939 vehicles came off the line. General Motors approached Lotus in 1986, which was part of GM then, and asked for their help developing a high-performance car to be based on the C4 Vette. Lotus then designed an engine, with the assistance of GM's Corvette team, to replace the original "push-rod" L98 V-8, which was the motor that powered the C4 Chevy Corvette.
The motor the designers created was an aluminum-block V-8 that had the
identical bore centers as the L98 but had 32 valves and four overhead
cams. Lotus also engineered an exclusive air-management system that
allowed the engine to shut off eight of the 16 fuel injectors and
intake runners when the motor was at part throttle. At full-throttle
the ZR1 developed 375 hp.
Having nowhere to produce the new engine, GM farmed out the project to Mercury Marine, a marine engine manufacturer located in Stillwater, Oklahoma.
The Lotus company also had a hand in developing the ZR1 "active suspension system." Called the FX3, it would become the basis for all Corvette (optional) suspension systems.
All ZR1s have a "valet key," which allows one to turn the engine power to "full," indicating full horsepower, or "normal," which disables the secondary intake ports and reduces horsepower to 200. The other differences between the ZR1 and stock models are the wider rear wheels and the location of the center rear stop lamp.