now on display in Pontiac showrooms, they were somewhat heavier than the production versions. That unfortunate fact accounts for the rather disappointing performance figures we recorded.
The Sprint six, a two-door hardtop with the 215-horsepower engine, four-speed Muncie gearbox and 3.55-to-1 rear axle gearing took 10.4 seconds to romp from zero to 60 mph and 17.5 seconds to cover the standing quarter mile. By way of comparison, we tested essentially the same Sprint power train in a heavier Tempest hardtop last summer and were able to cover the quarter in 15.8 seconds. We feel confident that a production Firebird Sprint will equal or better that latter figure.
Our Firebird 400 was a convertible with the big GTO engine, three-speed automatic transmission and 3.08 rear axle. Considering the heavier body type and the theoretically less efficient drive train, its performance was closer to what we would expect of a production equivalent. It took 7.2 second from zero to 60 and 15.5 seconds in the quarter mile.
The two body styles mentioned, incidentally, are the only ones available in the Firebird line. And, as far as interior accommodations, trunk volume and so forth are concerned, they’re exactly like the Camaro hardtop and convertible.
Pontiac, however, has come up with a way to use the trunk volume more effectively. Like most of Detroit’s sporty cars, the Firebird has an abbreviated rear deck that won’t hold very much luggage. However, as standard equipment, the car has a collapsible spare tire that permits what space is available to be put to better advantage.
When the square is deflated, it takes up only slightly more room than a bare wheel. Yet, when an accompanying bottle of compressed gas is applied to the tire, it blows up to full size.
The tire itself isn’t suitable for long distance, high speed use. But it is adequate to get the car to the next service station down the road where the faulty tire it’s replacing can be repaired.
Because some Firebird prospects are apt to view the collapsible spare with misgivings, Pontiac has made it a delete option. The customer can have a conventional spare in its place at no extra charge.
When only two passengers are aboard, the problem of storage space can be solved still another way. A folding rear seat back, similar to the type offered on both the Camaro and the Corvair, is available as an option.
The Firebird structure, like the Camaro, combines both separate and unitized elements. The engine, gearbox, front springing and steering are all attached to a sub-frame of lad_ der design that bolts to to the main body. The rear suspension, however, is mounted on framework that’s actually an integral part of the body.
The independent front springs are coils while the rear axle is suspended on single semi-elliptic springs like those of the Camaro – and the Chevy 11, for that matter. Pontiac has added its own refinement to the rear suspension, though, in the form of traction arms designed to control axle behavior.
Though Pontiac stylists started with the Camaro outline, they resolved to give the Firebird a distinct Pontiac took. Early taillight proposal had wraparound appearance, was toned down to simple, louvered pattern in final version. Leon, hungry look is evident even in early clay model.
Here, the features of the production Firebird are beginning to take shape, though this early prototype has a separate grille and front bumper and single headlight treatment. Louvered taillights seen at right are in sculptured, concave panel, not on flat, full-width surface.