1967 Pontiac Firebird Sprint OHC Versus Firebird 400 (Vintage Car Life Comparison): Overhead Cam Versus Cubic Inches

The Pontiac Firebird was a late introduction for 1967, but it attracted a lot of interest from the enthusiast press, especially the big-engine Firebird 400 and the Firebird Sprint, which was pitched as “a lightweight touring car” powered by the four-barrel version of the Pontiac OHC six. In August 1967, the editors of Car Life tried both and found that the Firebird 400 did a better job of delivering on its promises.

Although the first-gen Firebird was technically just a single model offered in two body styles (hardtop and convertible), Pontiac marketed it as a five-car lineup, distinguished by engines. Choices included the 230-cid Pontiac OHC six, in 165 hp base or 215 hp Sprint forms; the 326-cid V-8, in 250 hp two-barrel or 285 hp four-barrel versions; and finally the four-barrel 400-cid V-8, which had a nominal 325 hp with or without the optional Ram Air package.

Naturally, the car magazines were most interested in the Firebird 400, which had essentially a base GTO engine in a smaller package. However, there was also considerable interest in the OHC Firebird Sprint. Pontiac had first offered the belt-driven overhead cam six and Sprint package on the Tempest/Le Mans in 1966, but despite its technical novelties (which included a belt-driven camshaft and clever hydraulic valve lash adjusters), the hotter OHC six hadn’t seemed quite at home in the A-body intermediates, even on a European jaunt. Some observers had wondered what this engine could do in a smaller, lighter, more agile package. Now, Pontiac had obliged.

Car Life decided to test both the Sprint and the 400. This wasn’t really a head-to-head comparison — the Firebird 400 had an edge of more than 100 horsepower, so it was obviously going to triumph in any straight-line performance contest — but a test to see which high-performance ‘Bird best lived up to its marketing. “The Firebird Sprint is intended as the domestic answer to European Grand Touring machines, presumably Jaguar, Porsche and Mercedes, but at much lower cost,” the editors noted. “The Firebird 400 is, simply, a Supercar of somewhat diminutive proportions.”

The Firebird Sprint test car also had an interesting new option, which I wish this article would have examined more closely: radial tires. Standard tires for the Firebird were low-profile E70-14 Wide Ovals, but 185R14 radials were optional. This wasn’t the first use of radial tires on a domestic car (Oldsmobile was already offering them on the Cutlass Supreme, from the beginning of the 1967 model year), but radials were still uncommon on Detroit cars.

The first-gen Firebird was developed in haste, and its relationship to its Chevrolet Camaro, especially in 1967 and 1968, was obvious to most observers. Car Life remarked:

The major objection to Firebird appearance was that, “It looks just like a Camaro.” While there is no question as to the validity of this statement, the Firebird, taken on its own, is a well styled vehicle whose appearance promises performance in every sense of the word. The huge, flaring fender contours manage to make even E70-14 Wide Oval tires, standard on all Firebirds, appear slightly narrow. The test Sprint was equipped with 185R-14 radial ply tires, recently made available by Pontiac as a handling option. These tires were noticeably narrower in section than the Wide Ovals, and gave the car an almost “narrow track” appearance.

Firebird’s extended nose, most noticeable departure from Camaro styling, was viewed with mixed emotions by observers. The general consensus seemed to be that the long, pointed nose furthered the long hood look-of-power profile which has come into vogue with Ponycar packages. A minor parking shunt proved the protection afforded by this armored snout. Prospective Firebird owners are hereby advised that the front of this car is much farther away than is apparent from the driver’s seat.

Except for their engines and tires, the Firebird test cars were similarly equipped: Both had the optional 4-speed stick shift, power steering, power front disc brakes, the Custom interior, and hood-mounted tachometers.

Car Life had mixed feelings about the hood tach, which was showy and easy to see, but hampered by its “attraction for early morning dew, dust and raindrops.” It was also a tempting target for thieves and vandals — not an area where the GM F-bodies ever needed much help.

With either the Sprint or the 400, you got only a speedometer and a fuel gauge unless you separately ordered the Custom Gauge Cluster, which added coolant temperature and oil pressure and an ammeter in the right-hand binnacle. The Sprint test car had this option, which Car Life thought would reduce driver anxiety “during vigorous driving.” The downside, which the editors had complained about on the GTO, was that for some bizarre reason, Pontiac had arranged the temperature and oil pressure gauges to read backward: The needles fell as temperature or pressure rose, which might give a new owner some anxious moments.

Although the Sprint OHC six wasn’t the most powerful engine offered in the Firebird, the editors were very taken with its sound:

The great visual attraction of the test Sprint was aided by audible magnetism. There is something almost musical about the exhaust note of a highly tuned 6-cyl. engine, and the Firebird Sprint exhaust system does little to suppress this sound. While certainly legal, the decibel level of the Sprint exhaust adds to the European, sporting nature of this automobile.

Car Life was considerably less happy with the optional center console, which their Sprint had and their 400 did not:

A hard plastic sliding panel in the console caused an unpleasant amount of rattle, squeak and grind when running through the shift pattern. and apparently added its resistance to the shift mechanism. The 400, sans console, was a much better shifting automobile, and exhibited none of the noises of the Sprint. Effort in the 400 was about half that of the Sprint, and shifting the 400 was much more pleasant.

Even without the console, CL felt shift effort was too high with the 4-speed and were annoyed that it “required a lifting motion to negotiate the 2-3 shift.” They weren’t convinced that either the Sprint or the 400 really needed the 4-speed, except for drag strip use, and suggested that the standard all-synchro 3-speed would do just as well for a lot less money. Although they didn’t mention it, the more tempting alternative for the Firebird 400 would have been Turbo Hydra-Matic, which unfortunately wasn’t available on the Sprint or with the 326. (The two-speed automatic hampered the performance of the OHC six far more than TH400 penalized the big 400 engine.)

There were also some harsh editorial comments on the seats:

Seats in both Firebirds were very attractive, an appearance which was unfortunately not totally matched by their comfort. Cushions were rather thin and hard, and back angle too vertical. Seating position was judged poor, with respect to driving comfort. Steering wheel location was in the GM tradition, close to the driver’s chest. If seat adjustment permitted full depression of the clutch pedal, the driver’s arms were bent at much too great an angle to accommodate the too-close wheel position. It seems apparent that Detroit’s “sports car” designers haven’t spent much time in real ones.

Later in the text, the editors also complained that the back seat was largely uninhabitable except for little kids. The same was true of nearly all the pony cars, and buyers very clearly did not care. (Having slightly more back seat space didn’t help sales of the Plymouth Barracuda or later AMC Javelin one bit.)

On paper, both Firebird test cars should have had good stopping power, since both had the optional front disc brakes. Unfortunately, on the test track, their braking performance proved terrifying, with hard stops resulting in severe loss of control:

These brakes were judged overly sensitive, requiring low pedal pressure to lock the wheels, and were poorly balanced, front to rear. One of CL’s standard brake test procedures consists of determining maximum deceleration rate from 80 mph. This test proved thrilling: Rear wheel lockup was almost unavoidable when high deceleration rates were attempted. Normal fade testing was not performed, because the question of brake fade seemed academic in view of the almost total loss of vehicle control encountered during initial hard stops. Some means of preventing rear wheel lockup is mandatory, if high-speed, high-deceleration stops are to be made acceptable.

The problem was proportioning: Caliper disc brakes need more line pressure than drums for the same deceleration force, so braking hard enough to get the discs to bite tends to cause the rear drums to lock up completely, absent some system to prevent it. When Ford had introduced front discs for the Thunderbird, Continental, and Mustang for 1965, they had included a proportioning valve that would limit pressure to the rear brakes until the front brakes were more firmly engaged. This still wasn’t a complete solution (Car Life had found that the disc-braked Mustang still tended to lock its rear wheels abruptly), but trying to get by without even this simple measure was disastrous. Disc-braked 1967 Chrysler products suffered the same problem for the same reason.

Front discs were seldom ordered on the 1967 Firebird and Camaro, and for once, that might’ve been just as well.

Car Life found the performance of their Sprint OHC engine somewhat less than anticipated:

The Sprint’s ohc Six incorporated 4-barrel carburetion, 10.5:1 compression, high-performance camshaft and the aforementioned split exhaust system. On paper then, one would expect a free-breathing, high-revving engine with substantial power output. In practice, valve float occurred at approximately 6100 rpm, well short of the tachometer redline at 6500. Acceleration from 5000 rpm upward was slow, and felt flat. Torque at low speeds was adequate, perhaps more than would be expected from engine specifications. Power at high engine speeds, however, never developed. The engine had a feeling of being just about to “turn on,” but never did. In fairness to the test Sprint, its previous history was one of abuse and improper break-in. Also, the Sprint engine was equipped with the full California emission-reduction package. Whatever the specific cause, the test car did not perform up to our expectations.

A problem the car magazines frequently suffered in this era was that most of their test cars came from a press fleet provided by the automakers’ local public relations offices. While this fleet did include the occasional ringer, specially massaged for maximum power, most of the press cars were put through the ringer, used hard by unsympathetic buff book testers and indifferently tuned. Normal Car Life editorial policy was to run cars as they were received, but at times, their test cars were pretty clearly not in the best of mechanical health.

The editors had no such trouble with the Firebird 400, which also lacked the Sprint engine’s air injection system:

The 400-cu. in./325-bhp engine is a beautifully flexible, quiet, tremendously responsive powerplant. Around town, the only difficult task was avoiding flagrant speed limit violation. The engine seemed quite happy motoring along just above idle, but a few periods of this sort of operation did foul spark plugs. Once on the open road, a few bursts of speed cleared the plugs, and the 400 flexed its muscles. Acceleration was impressive in any gear, at almost any speed. The Firebird 400 would pull strongly to just over 5000 rpm, where hydraulic lifter pump-up was encountered. In high gear, the 400 would run out to valve float in an amazingly short period of time.

A quarter-mile elapsed time of 14.7 sec. is exceptional for an automobile in full street trim, with two passengers and test gear aboard. Only the 427 Corvette, and Hemi-powered Plymouths and Dodges are capable of times quicker than this, and that places the Firebird 400 in the very uppermost echelon of domestic Supercars.

Theoretically, the Firebird version of the 400 engine included a modified throttle linkage that accounted for its 10 hp deficit compared to the same engine in the GTO, allowing Pontiac to pay lip service to corporate policy limiting compacts and intermediates to no more than one advertised horsepower per 10 lb of car weight. This change went suspiciously unmentioned in contemporary road tests, and it seems likely that the press cars had the throttle linkage altered to allow the carburetor secondaries to open fully, which was apparently a very simple exercise.

Here are some highlights from the Car Life acceleration tests:

• 0 to 30 mph: Sprint: 3.6 sec.; 400: 2.9 sec.
• 0 to 60 mph: Sprint: 10.0 sec.; 400: 6.5 sec.
• 0 to 100 mph: Sprint: 32.5 sec.; 400: 15.5 sec.
• Standing quarter mile: Sprint: 17.5 sec. at 80 mph; 400: 14.7 sec. at 98 mph

In addition to the obstructive shifter and whatever may have been amiss with the OHC engine, Car Life found their Sprint test car hampered by severe axle control problems. Both test cars had single-leaf rear springs with two trailing arms, but the stiffer rear springs of the 400 apparently did a better job of keeping the axle in place. In the Sprint, CL found, “Takeoff was accompanied by a period of violent hop, unless a very gentle ‘roll-out’ was employed.”

Despite all that, their Firebird Sprint’s recorded acceleration times were still quite good. Their test car was almost a second and a half quicker to 60 mph than a 1967 Camaro with the 250-cid pushrod six, and almost as quick as a Mustang with the 225 hp 289-4V. I don’t think Car Life ever tested a Firebird with the 326, but Motor Trend did, and found that the 4-speed Sprint was a bit quicker than a 326-2V with automatic, though not as fast as the 326 H.O.

Both the Sprint and the Firebird 400 handled well on smooth roads. Car Life called Sprint “just plain fun,” with a surprising amount of final oversteer when pressed. The 400 understeered more, although it was easy to bring the tail out by applying more power. However, the editors felt both cars were handicapped by the overly light power steering, whose lack of feel made it too easy to over-correct in fast maneuvers.

The Firebird’s agility did come at a cost:

The Sprint delivered the same sort of rock-solid, back-slapping ride familiar to early post WW II sports cars. To those who associate ride firmness with superior handling, the Firebird meets their requirements. Most obvious among ride deficiencies in both Firebirds was a lack of free spring travel. The springs were forced to absorb all road irregularities in about 3 in. of travel, and if the bump was too severe to allow the stiff springs to accommodate it, the jounce bumpers entered the picture with a resounding bang. Other manufacturers, principally in Europe, have caused live axle layouts to produce a very comfortable ride while providing superb handling. Pontiac has not.

Of course, buyers of cars like these weren’t looking for a cushy ride, but Car Life warned that the Firebird’s lack of rear suspension compliance caused the rear wheels “to skate across rough roads both during cornering and on acceleration at low speeds.”

The editors, like their colleagues at Road & Track (which was then under common ownership), were somewhat disappointed with the Sprint:

The Firebird Sprint, then, was an exciting car to drive hard on smooth roads. It was not particularly fast or economical, delivering less than 14 mpg during testing. It was not particularly comfortable, though turnpike or smooth highway ride was acceptable. An enjoyable car? Yes! An attractive car? Yes! A reliable car? Undoubtedly! A European-style GT car? No!

Ultimately, they may just have expected too much. The Firebird Sprint wasn’t as much lighter than the A-body Le Mans Sprint as you might assume — Car Life‘s 4-speed tester had a curb weight of 3,470 lb — and its rear suspension certainly wasn’t any more sophisticated.

The Firebird 400 came closer to fulfilling its advertised goals than did the Sprint. The 400 is the most powerful, fastest of the Firebird family, and one of the fastest of Ponycars. Preceding comments on ride and handling apply to the 400 as much as they do to the test Sprint. The Firebird 400 exhibited slightly more understeer at low speeds, but could easily be placed into power oversteer attitude with a nudge on the accelerator pedal. Ride quality of the 400 was slightly superior to the Sprint, but still quite vintage. …

The 400 is likely to be the enthusiast’s choice among Firebird’s lineup. It was definitely CL’s choice of the two test cars. The 400 simply made more sense. Neither car was a sports car, although both compare favorably in handling ability with others in the Ponycar brigade. … To the average American purchaser, particularly one inclined toward Firebird-type vehicles, acceleration makes up for numerous faults. The Firebird 400 has acceleration, in spades.

Buyers did strongly prefer the Firebird 400 to the Sprint (by a margin of 18,698 to 7,210 for 1967), but neither sold nearly as well as the mild-mannered 326-2V, which cost $10.56 less than the Sprint and $178.79 less than the Firebird 400.

The buff books mostly ignored the Firebird 326, but in retrospect, it seemed closest to what many pony car buyers really wanted: neither a sports car, a European-style GT, nor a muscle car, just a stylish coupe offering sporty image and un-stressed performance at a reasonable price.

 

Related Reading

Vintage R&T Road Test: 1967 Pontiac Firebird Sprint – “European-Style Driving Machine? — Hardly” (by Paul N)

1967 Firebird Convertible – With The Rare And Special OHC Inline-Six (by J P Cavanaugh)

Driveway Find: 1967 Pontiac Firebird – Hot Street Machine (by Rich Baron)

Car Show Classic: 1967 Pontiac Firebird – Coulda Had A V8; Didn’t Want One (by Tom Klockau)

In-Motion Classic: 1967 Pontiac Firebird 400 Convertible – In Season (by Joseph Dennis)