The iconic 1964 Pontiac GTO didn’t materialize overnight. Its origins can be traced back to the early 1960s, specifically to the innovative and often overlooked 1961-1963 Pontiac Tempest. John Z. DeLorean, a key figure behind the GTO, had been strategically developing the Tempest as a true American grand touring car for several years. The 1961 Tempest was a bold first step, featuring half of the future GTO’s potent 389 V8 engine, including an optional high-performance four-barrel carburetor version. Adding to its forward-thinking design was a rear transaxle coupled with independent rear suspension, a feature DeLorean championed, even if the Corvair-derived swing axles weren’t without their limitations.
For the 1963 model year, Pontiac refined the Tempest formula. They discontinued the rarely chosen Buick 215 aluminum V8 and instead introduced a smaller bore variant of the robust 389 V8. Initially presented with a modest two-barrel carburetor, this engine was advertised as a 326 cubic inch unit, producing 260 horsepower. However, as 1963 progressed and the GTO project gained momentum, a higher-output version with a four-barrel carburetor, delivering 280 horsepower, became available.
This article delves into the 1963 Pontiac Tempest, focusing on a 260 horsepower model equipped with a two-speed automatic transmission. While not yet the full-fledged muscle car that the GTO would become, the ’63 Tempest was already hinting at the performance potential that Pontiac was brewing.
Alt text: Front three quarter view of a light blue 1963 Pontiac Tempest LeMans coupe showcasing its clean lines and dual headlights.
The Mystery of the 326 (Actually 336) Engine
Interestingly, the engine marketed as a 326 cubic inch actually displaced a larger 336.66 cubic inches. The reason behind Pontiac’s 326 designation remains somewhat of an enigma. GM’s mandate restricting intermediate cars to a maximum of 330 cubic inches didn’t come into effect until 1964. For the ’64 Tempest, the bore was indeed reduced to create a genuine 326 cubic inch engine. However, this displacement rule was famously disregarded with the introduction of the 389 cubic inch GTO. This discrepancy adds an intriguing layer to the 1963 Tempest’s narrative.
Alt text: Original 1963 Pontiac Tempest advertisement highlighting its styling, economy, and roadability.
A Mid-Size Marvel with Surprising Power
The 1963 Tempest LeMans could be considered a slightly smaller, more budget-conscious version of the Pontiac Grand Prix. The ’63 Tempest’s redesigned, longer, and wider body panels visually elevated it into a true mid-size category, even though it shared its fundamental body structure with the earlier models and had strong Corvair influences. Despite its size, the 326 engine delivered ample power. Driving the 1963 Tempest quickly dispels any notion that it needed the larger 389 immediately. The 326 provided more than enough power to readily induce wheelspin, demonstrating its inherent performance capabilities.
Alt text: Side profile of a 1963 Pontiac Tempest LeMans hardtop showcasing its elongated body and chrome trim.
Transmission and Drivetrain
The two-speed automatic transmission in the 1963 Tempest shared lineage with the Chevrolet Powerglide, but it was an evolution of the ’61-’62 “Tempest-Drive” system. This updated unit offered smoother shifting and was generally regarded as an improvement over its predecessor, having eliminated the torque-splitting top gear feature.
Alt text: Rear quarter view of a red 1963 Pontiac Tempest convertible emphasizing its rear styling and soft top.
However, the combination of the torque converter automatic and the 3.09 rear axle ratio resulted in significant torque multiplication, sometimes overwhelming the narrow 6.50-15 tires. Aggressive throttle input, even mid-turn, could easily provoke the rear end to swing out. A taller (numerically lower) axle ratio was advisable for more controlled handling. Despite a common misconception popularized by the movie “My Cousin Vinny,” the 1963 Tempest did not offer a limited-slip differential. It’s speculated that the absence of the ’62 Corvair’s Positraction unit was due to the necessity of a larger, stronger differential to handle the V8 engine’s torque.
Alt text: Close up detail of the 1963 Pontiac Tempest’s rear badging and taillights.
Alt text: Interior shot of a 1963 Pontiac Tempest showcasing the dashboard, steering wheel, and bench seat.
Performance and Driving Experience
“Driving a car with so much power is, of course, great fun,” as noted in period reviews. The 260 horsepower Tempest achieved a 0-60 mph time of around 9.5 seconds. While not groundbreaking, this was respectable performance for the era. A version equipped with the three-speed manual transmission, tested by Popular Science, demonstrated quicker acceleration, reaching 60 mph in a brisk 8.1 seconds. This manual transmission model was reported to have a 3.90:1 rear axle ratio, although this wasn’t listed as a standard option in brochures.
Alt text: Engine bay of a 1963 Pontiac Tempest displaying the 326 V8 engine and surrounding components.
The later-released 280 horsepower, four-barrel carburetor 326 HO version was even more potent. Car Life tests recorded a 0-60 mph time of just under 7 seconds and a quarter-mile time of 17 seconds. This 0-60 time closely approached the performance figures of the ’64 GTO, although the quarter-mile time was slightly slower.
Alt text: Front quarter view of a white 1963 Pontiac Tempest LeMans highlighting its grille and front fender design.
At highway speeds, around 80 mph, the Tempest felt relaxed and “loafing,” giving the impression of a larger car. However, the ride quality and levels of road and engine noise didn’t quite match that of a full-size car, likely due to its unibody construction. The power steering, with approximately five turns lock-to-lock, was considered too slow. Additionally, the 9-inch drum brakes were deemed adequate but marginal, suggesting room for improvement.
Alt text: Side view of a 1963 Pontiac Tempest showcasing its overall proportions and wheel design.
The four-speed manual transmission from the Corvair was deemed insufficient for the V8’s power. Consequently, a three-speed manual was the sole manual option. However, with the engine’s abundant torque in a relatively lightweight car, the absence of a fourth gear was arguably not a major drawback, except perhaps in racing scenarios. Even the three-speed manual was reported to be somewhat fragile, with instances of damage from enthusiastic gear changes.
Alt text: Detailed view of the 1963 Pontiac Tempest instrument panel with its four round gauges and chrome accents.
Interior and Suspension Refinements
The 1963 Tempest featured a new and visually appealing instrument panel with four prominent round openings. However, the layout of the gauges was not considered entirely optimal. The fact that the Tempest utilized a cabin design essentially shared with the Corvair is a testament to the Corvair’s surprisingly spacious interior.
Alt text: Front view of a 1963 Pontiac Tempest Deluxe model highlighting its chrome grille and headlight bezels.
Alt text: Close up view of the 1963 Pontiac Tempest LeMans emblem on the front fender.
Alt text: Rear view of a 1963 Pontiac Tempest showcasing its taillights, rear bumper, and trunk lid.
Subtle changes were made to the rear suspension for 1963. While still employing swing axles, the system now utilized L-shaped control arms instead of semi-trailing arms. This modification aimed to reduce toe-in variations during camber changes. The Tempest had developed a reputation for somewhat unpredictable rear-end behavior, particularly snap oversteer at its handling limits. The ’63 revision offered a marginal improvement but didn’t fully resolve the issue. A camber-compensating spring, similar to what was implemented in the ’64 Corvair, would have been a more effective solution. Interestingly, handling was not extensively discussed in period road tests, perhaps out of a reluctance to dwell on the Tempest’s known handling quirks, or possibly because test drives didn’t push the car to its limits.
Alt text: Angled side view of a 1963 Pontiac Tempest LeMans coupe parked on a street, capturing its stance and design details.
The Tempest’s Enduring Legacy
The overall assessment of the 1963 Tempest was positive, despite some reservations about its increasing size. However, this growth was simply a prelude to the 1964 Tempest and the entirely new GM A-body platform. These new models represented a significant shift for GM, prioritizing performance and paving the way for the muscle car era. The ’64 and subsequent GM A-bodies marked the beginning of a major transformation for GM, as these cars and their successors ultimately surpassed full-size cars in sales. Therefore, the ’63 Tempest was far more than just a warm-up act for the GTO; it was a pivotal vehicle that initiated a revolution in the automotive landscape.
Alt text: Full side view of a 1963 Pontiac Tempest LeMans convertible, showcasing its long profile and elegant design.
Alt text: Rear three quarter view of a 1963 Pontiac Tempest LeMans hardtop with its distinctive roofline and rear styling.
Further Reading on the 1963 Pontiac Tempest and Related Models:
- Curbside Classic: 1963 Pontiac Tempest LeMans – Pontiac Tries To Build A BMW Before BMW Built Theirs, And Almost Succeeds
- CC BS Buster: “My Cousin Vinny” Courtroom Scene – The 1963 Tempest Actually Did Not Have A Limited Slip Differential and The ’64 Skylark Did
- Automotive History: 1963 Days – Popular Science Tests the Hot Compacts
- Vintage Car Life Road Test: 1964 Pontiac GTO – “Honest In Performance”?
- Magnificent Kludge: The ‘Rope-Drive’ 1961–1963 Pontiac Tempest (Ate Up With Motor in-depth analysis of the ’61-’63 Tempest)
