The DeSoto Fireflite III Convertible, powered by a 5.6-liter V8 engine and TorqueFlite automatic transmission, represented a significant offering in the American luxury car market during its brief production run from 1956 to 1957. Positioned as a premium model within the DeSoto lineup, the Fireflite aimed to combine stylish design with robust performance. It was part of the broader third generation of the Fireflite, which saw a complete redesign emphasizing longer, lower, and wider styling in line with the automotive trends of the mid-1950s. The convertible body style, in particular, was intended to appeal to buyers seeking an open-air driving experience with a touch of elegance.
Technical Specifications
| Brand | DeSoto |
| Model | Fireflite |
| Generation | Fireflite III Convertible |
| Type (Engine) | 5.6 V8 (295 Hp) TorqueFlite |
| Start of production | 1956 |
| End of production | 1957 |
| Powertrain Architecture | Internal Combustion engine |
| Body type | Cabriolet |
| Seats | 6 |
| Doors | 2 |
| Fuel Type | Petrol (Gasoline) |
| Power | 295 Hp @ 4600 rpm |
| Power per litre | 52.8 Hp/l |
| Torque | 508 Nm @ 2800 rpm / 374.68 lb.-ft. @ 2800 rpm |
| Engine Model/Code | S26 |
| Engine displacement | 5588 cm3 / 341 cu. in. |
| Number of cylinders | 8 |
| Engine configuration | V-engine |
| Cylinder Bore | 96.01 mm / 3.78 in. |
| Piston Stroke | 96.52 mm / 3.8 in. |
| Compression ratio | 9.25:1 |
| Number of valves per cylinder | 2 |
| Fuel injection system | Carburettor |
| Engine aspiration | Naturally aspirated engine |
| Valvetrain | OHV |
| Engine oil capacity | 4.7 l / 4.97 US qt | 4.14 UK qt |
| Coolant | 19.9 l / 21.03 US qt | 17.51 UK qt |
| Fuel tank capacity | 87 l / 22.98 US gal | 19.14 UK gal |
| Length | 5537 mm / 217.99 in. |
| Width | 1986 mm / 78.19 in. |
| Height | 1448 mm / 57.01 in. |
| Wheelbase | 3200 mm / 125.98 in. |
| Front track | 1549 mm / 60.98 in. |
| Rear (Back) track | 1516 mm / 59.69 in. |
| Front overhang | 879 mm / 34.61 in. |
| Rear overhang | 1458 mm / 57.4 in. |
| Ride height (ground clearance) | 137 mm / 5.39 in. |
| Minimum turning circle (turning diameter) | 13.1 m / 42.98 ft. |
| Approach angle | 17.7° |
| Departure angle | 13.3° |
| Ramp-over (brakeover) angle | 9.8° |
| Drivetrain Architecture | The Internal combustion engine (ICE) drives the rear wheels of the vehicle. |
| Drive wheel | Rear wheel drive |
| Number of gears and type of gearbox | 3 gears, automatic transmission TorqueFlite |
| Front suspension | Independent coil spring |
| Rear suspension | Leaf spring |
| Steering type | Worm-reduction unit |
Powertrain & Engine Architecture
The heart of the Fireflite III Convertible was the DeSoto S26 5.6-liter (341 cubic inch) V8 engine. This engine featured a cast iron block and aluminum cylinder heads, utilizing an overhead valve (OHV) configuration. It was equipped with a single Carter carburetor, providing fuel delivery. The 9.25:1 compression ratio contributed to the engine’s respectable 295 horsepower output at 4600 rpm and 374.68 lb-ft of torque at 2800 rpm. The TorqueFlite automatic transmission, a three-speed unit, was the sole transmission option for the Fireflite III Convertible. This transmission was known for its smoothness and durability, and it played a key role in delivering the engine’s power to the rear wheels.
Driving Characteristics
The combination of the 5.6-liter V8 and the TorqueFlite automatic transmission provided a comfortable and capable driving experience. While not a sports car, the Fireflite III Convertible offered brisk acceleration for its time. The automatic transmission, while smooth, did result in some power loss compared to a manual transmission. The gear ratios were optimized for cruising, making it well-suited for highway driving. The relatively heavy weight of the vehicle, typical of American cars of the era, meant that handling was not particularly sharp, but the independent front suspension did provide a reasonably comfortable ride.
Equipment & Trim Levels
The Fireflite III Convertible was well-equipped for its price point. Standard features included power steering, power brakes, a heater, and a deluxe interior with cloth and vinyl upholstery. Optional extras included power windows, a power seat, a radio, and whitewall tires. The interior featured a spacious cabin with seating for six passengers, although rear seat space was somewhat limited. The dashboard was typically adorned with chrome trim and featured a combination of analog gauges.
Chassis & Braking
The Fireflite III Convertible utilized a body-on-frame construction, common for American cars of the 1950s. The front suspension was independent, employing coil springs, while the rear suspension was a traditional leaf spring setup. This configuration provided a comfortable ride, but it wasn’t particularly sophisticated in terms of handling. The braking system consisted of drum brakes on all four wheels. While adequate for the time, the drum brakes lacked the stopping power of modern disc brakes.
Market Reception & Comparison
The DeSoto Fireflite III Convertible was generally well-received by critics, who praised its stylish design, comfortable ride, and powerful engine. However, it faced stiff competition from other American luxury cars, such as the Buick Roadmaster and the Oldsmobile 98. Compared to these rivals, the Fireflite offered a similar level of luxury and performance, but it lacked the brand recognition of some of its competitors. Fuel economy was typical for a large American car of the era, averaging around 15-18 miles per gallon. Reliability was generally good, but maintenance costs could be high due to the complexity of the engine and transmission.
Legacy
The DeSoto Fireflite III Convertible represents a significant chapter in American automotive history. While DeSoto as a brand ultimately disappeared in 1961, the Fireflite remains a sought-after classic car among collectors. The 5.6-liter V8 engine and TorqueFlite transmission proved to be durable and reliable powertrains, and many examples are still on the road today. The Fireflite’s combination of style, comfort, and performance continues to appeal to enthusiasts, and it serves as a reminder of the golden age of American automobiles. Finding parts can be challenging, but a dedicated network of suppliers caters to the classic DeSoto market, ensuring that these vehicles can be preserved for future generations.
