Although General Motors supported the ban on racing proposed by the American Automobile Association (the result of a 1955 crash in France that killed 77 people), Zora Duntov and his Chevrolet Corvette designers thought Vette owners would still compete. Therefore, in 1963 his team developed a special performance package aimed at “certain” Chevy V8 racers.
Known as the RPO Z06, it was comprised of larger-than-stock shocks,
stiffer springs, metallic brake linings with power drums cooled by
vented backing plates and front air scoops, a dual master brake
cylinder, a brake booster, and a bigger-than-stock anti-roll bar. The
package also initially included an enormous 36.5 gallon gas tank (20
gallon was standard). The thought was to use these Corvettes, which
were known as “Big Tanks,” in races like Daytona and Sebring. The first
packages were only offered on coupes because this tank would not fit on
the convertible. The engine was a 327-cubic inch L84 that featured
Rochester fuel injection and developed 360 hp.
The Z06 performance
package added $1818 to the $4252 base price of the coupe. The price
came down after a while and Chevrolet stopped including the big gas
tank. Now buyers could also purchase the package for convertibles as
After Ford opted out of the racing ban, GM quickly followed.
Z06 packages were already prevalent in the racing scene when Duntov and
his team began work on a new Corvette which would become known as the
Grand Sport, which employed Z06 components. After Z06 came ZR-1, also
known as “Zora’s Racers.”