In under a decade, GM’s small-block received a substantial boost in displacement while also becoming the standard-bearer for several new internal developments in engine technology. These developments ultimately produced a new crop of small-block powerplants based on Chevrolet’s new 327 cubic-inch engine platform. Of the four 327 cubic-inch small blocks available in 1964, none topped the output of the fuel-injected L84 V8.
The first Z06 was actually an option package first offered with the 1963 Corvette. The package was developed by Corvette's legendary lead engineer and racing advocate Z0ra Arkus-Duntov. The Z06 option was designed to allow consumers to bolster the 1963 "Split-Window" Corvettes performance and handling capabilities for use on the race track. Selecting regular production option (RPO) Z06 when ordering a Corvette resulted in a car equipped with some tasty options.
The L84 was the most powerful 327 available for the 1965 Corvette thanks to its Ram-Jet Fuel Injection which was an expensive $538 option. For competition, race customers had a range of options available to them including the N03 36-Gallon Fuel Tank, closer rear axle ratios and the C48 Heater/Defroster Delete (-100).