Jay Leno shows off his rare 1968 Pontiac Firebird Sprint six-cylinder car.

The 1960s are often referred to as the golden age of American muscle cars, but the 1968 Pontiac Firebird Sprint featured in this edition of Jay Leno's Garage shows that Detroit automakers were not only concerned with V-8 engines and quarter-mile times. It shows that Detroit automakers were not obsessed only with V-8 engines and quarter-mile times.

Instead of the V-8 engine found in other performance versions of the Firebird, the Sprint had an inline 6-cylinder engine under its hood. This was an upgraded version of the engine found in the base version of the Firebird, with a single overhead cam head, four-barrel carburetor, and performance exhaust. In the Sprint, it was mated to a four-speed manual transmission, which the driver operated with the assistance of a hood-mounted tachometer.

As Leno tells it, then-Pontiac boss John DeLorean was a fan of the Jaguar E-Type (introduced in 1961 with a dual overhead cam inline six-cylinder) and wanted to build a competitor. Pontiac eventually built a concept version called the Banshee, but General Motors did not approve a production model for fear of competing with the Corvette.

Instead, DeLorean introduced the Firebird Sprint, intending to compete with the E-Type with its own inline six-cylinder engine. Because the Firebird Sprint was intended to compete with European sports cars, it was even badged "4.1 liter," rather than the cubic-inch displacement that was common among American automakers at the time.

The Firebird Sprint may have satisfied DeLorean's legendary ego, but it was not a commercial success. It was less powerful than the V-8 Firebirds of the time (about 220 hp) but cost more, Leno noted. As a result, the Sprint is now very rare. Remember that there was no equivalent version of the Chevrolet Camaro, which twinned with the Firebird and shared GM's F-body platform.

Reno acquired the Firebird Sprint Convertible in 2019 and put it back on the road after a light restoration and some modern upgrades for drivability. To learn more about this rare Pontiac and hear its straight-six sing, watch the full video.