The DeSoto Firesweep I 4-Door Sportsman, equipped with a 5.3-liter V8 engine and TorqueFlite automatic transmission, represented a significant offering from the Chrysler Corporation’s DeSoto division during the 1956 and 1957 model years. Positioned as a mid-range offering within the Firesweep lineup, it aimed to blend style, comfort, and performance for the American family. This particular variant, producing 245 horsepower, was designed to appeal to buyers seeking a step up from base models while remaining within a reasonable price point. The Firesweep was DeSoto’s full-size offering, intended to compete with models from Buick, Oldsmobile, and Mercury.
Technical Specifications
| Brand | DeSoto |
| Model | Firesweep |
| Generation | Firesweep I 4-Door Sportsman |
| Type (Engine) | 5.3 V8 (245 Hp) TorqueFlite |
| Start of production | 1956 |
| End of production | 1957 |
| Powertrain Architecture | Internal Combustion engine |
| Body type | Sedan |
| Seats | 6 |
| Doors | 4 |
| Fuel Type | Petrol (Gasoline) |
| Power | 245 Hp @ 4400 rpm |
| Power per litre | 46 Hp/l |
| Torque | 434 Nm @ 2400 rpm / 320.1 lb.-ft. @ 2400 rpm |
| Engine Model/Code | S27 |
| Engine displacement | 5326 cm3 / 325.01 cu. in. |
| Number of cylinders | 8 |
| Engine configuration | V-engine |
| Cylinder Bore | 93.73 mm / 3.69 in. |
| Piston Stroke | 96.52 mm / 3.8 in. |
| Compression ratio | 8.5:1 |
| 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 | 76 l / 20.08 US gal | 16.72 UK gal |
| Length | 5481 mm / 215.79 in. |
| Width | 1986 mm / 78.19 in. |
| Height | 1440 mm / 56.69 in. |
| Wheelbase | 3099 mm / 122.01 in. |
| Front track | 1547 mm / 60.91 in. |
| Rear (Back) track | 1516 mm / 59.69 in. |
| Front overhang | 925 mm / 36.42 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 | 18.9° |
| Departure angle | 12.9° |
| Ramp-over (brakeover) angle | 10.2° |
| 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 Firesweep I 4-Door Sportsman was the DeSoto S27 5.3-liter (325 cubic inch) V8 engine. This engine featured a cast iron block and cylinder heads, with a 8.5:1 compression ratio. It utilized a single Carter carburetor for fuel delivery, and an overhead valve (OHV) valvetrain. The engine was designed for smooth operation and reasonable power output, prioritizing drivability over outright performance. The TorqueFlite automatic transmission, a three-speed unit, was a key component of the powertrain. It was known for its smooth shifting and durability, and was a popular choice for American cars of the era. The TorqueFlite’s design allowed for relatively quick acceleration, although it wasn’t geared for maximizing fuel economy.
Driving Characteristics
The 245 horsepower and 320 lb-ft of torque provided by the S27 V8 and TorqueFlite combination delivered adequate performance for the time. While not a sports car, the Firesweep offered brisk acceleration and comfortable cruising speeds. The automatic transmission, while smooth, did result in some power loss compared to the available manual transmission options. The gear ratios were optimized for everyday driving, with a focus on providing sufficient torque for passing and hill climbing. Compared to the higher-output DeSoto engines, this variant felt less aggressive, but it offered a more relaxed and refined driving experience. The rear-wheel drive configuration provided predictable handling, typical of American cars of the 1950s.
Equipment & Trim Levels
The Firesweep I 4-Door Sportsman with the 5.3L V8 and TorqueFlite transmission came standard with a respectable array of features for the mid-1950s. These included full wheel covers, a two-tone paint scheme, a spacious interior upholstered in cloth and vinyl, and a heater. Power steering and power brakes were often optional extras. The dashboard featured a combination of analog gauges, including a speedometer, fuel gauge, and temperature gauge. The interior trim was generally conservative, reflecting the DeSoto’s positioning as a family-oriented vehicle. Optional extras could include a radio, air conditioning (a relatively rare option at the time), and upgraded upholstery.
Chassis & Braking
The Firesweep I rode on a traditional body-on-frame chassis. The front suspension utilized independent coil springs, providing a comfortable ride. The rear suspension employed leaf springs, which were robust and capable of handling the car’s weight. Braking was accomplished via drum brakes on all four wheels, although some later models may have featured front disc brakes as an option. Steering was handled by a worm-reduction unit, which provided relatively heavy but precise steering feel. The chassis was designed for durability and comfort, rather than sporty handling.
Market Reception & Comparison
The DeSoto Firesweep I 4-Door Sportsman with the 5.3L V8 and TorqueFlite transmission was generally well-received by automotive critics. It was praised for its comfortable ride, spacious interior, and smooth-shifting automatic transmission. However, some critics noted that the engine lacked the punch of some of its competitors, and that the styling, while attractive, was not as bold as some other models. Compared to other Firesweep trims, this variant offered a good balance of performance and affordability. The 1.8L engine was more economical, but lacked the power for comfortable highway cruising. The higher-output V8s offered more performance, but came at a higher price.
Legacy
The DeSoto Firesweep I 4-Door Sportsman, while not a long-lived model, represents a significant chapter in American automotive history. The 5.3L V8 and TorqueFlite transmission proved to be relatively reliable powertrains, and many examples are still on the road today. However, parts availability can be a challenge, and restoration projects can be costly. The Firesweep is now considered a classic car, and is sought after by collectors and enthusiasts who appreciate its styling, comfort, and historical significance. The TorqueFlite transmission, in particular, is known for its durability and is often regarded as one of the best automatic transmissions of its era.
