The Mercedes-Benz W113 series, marketed as the SL “Pagoda” due to its distinctive roofline, represented a significant evolution in the SL lineage. Produced from 1963 to 1971, it aimed to blend the sporty character of the previous 300 SL with increased comfort and refinement. The 250 SL, introduced in November 1966 and continuing through January 1968, occupied a crucial middle ground within the W113 range. It replaced the earlier 230 SL and served as a stepping stone to the later 280 SL, offering a balance of performance and luxury. This variant, equipped with the M129 engine and an automatic transmission, was aimed at buyers seeking a sophisticated grand tourer rather than an outright sports car.
Technical Specifications
| Brand | Mercedes-Benz |
| Model | SL |
| Generation | SL Coupe (W113) |
| Type (Engine) | 250 SL (150 Hp) Automatic |
| Start of production | November, 1966 |
| End of production | January, 1968 |
| Powertrain Architecture | Internal Combustion engine |
| Body type | Coupe |
| Seats | 2 |
| Doors | 2 |
| Fuel consumption (combined) | 11.2 l/100 km (21 US mpg, 25.2 UK mpg, 8.9 km/l) |
| Fuel Type | Petrol (Gasoline) |
| Acceleration 0 – 100 km/h | 10.6 sec |
| Acceleration 0 – 62 mph | 10.6 sec |
| Acceleration 0 – 60 mph | 10.1 sec |
| Maximum speed | 195 km/h (121.17 mph) |
| Weight-to-power ratio | 9.1 kg/Hp, 110.3 Hp/tonne |
| Weight-to-torque ratio | 6.3 kg/Nm, 158.8 Nm/tonne |
| Power | 150 Hp @ 5500 rpm |
| Power per litre | 60.1 Hp/l |
| Torque | 216 Nm @ 4200 rpm (159.31 lb.-ft. @ 4200 rpm) |
| Engine layout | Front, Longitudinal |
| Engine Model/Code | M 129 III / 129.982 |
| Engine displacement | 2496 cm3 (152.32 cu. in.) |
| Number of cylinders | 6 |
| Engine configuration | Inline |
| Cylinder Bore | 82 mm (3.23 in.) |
| Piston Stroke | 78.8 mm (3.1 in.) |
| Compression ratio | 9.5:1 |
| Number of valves per cylinder | 2 |
| Fuel injection system | Multi-port manifold injection |
| Engine aspiration | Naturally aspirated engine |
| Valvetrain | SOHC |
| Engine oil capacity | 5.5 l (5.81 US qt | 4.84 UK qt) |
| Coolant | 12.9 l (13.63 US qt | 11.35 UK qt) |
| Kerb Weight | 1360 kg (2998.29 lbs.) |
| Max. weight | 1715 kg (3780.93 lbs.) |
| Max load | 355 kg (782.64 lbs.) |
| Trunk (boot) space – minimum | 340 l (12.01 cu. ft.) |
| Fuel tank capacity | 82 l (21.66 US gal | 18.04 UK gal) |
| Length | 4285 mm (168.7 in.) |
| Width | 1760 mm (69.29 in.) |
| Height | 1295 mm (50.98 in.) |
| Wheelbase | 2400 mm (94.49 in.) |
| Front track | 1484 mm (58.43 in.) |
| Rear (Back) track | 1485 mm (58.46 in.) |
| 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 | 4 gears, automatic transmission |
| Front suspension | Double wishbone, Transverse stabilizer |
| Rear suspension | Trailing arm |
| Front brakes | Disc |
| Rear brakes | Disc |
| Assisting systems | ABS (Anti-lock braking system) |
| Steering type | Cone worm with recirculation balls |
| Wheel rims size | 6J x 14 |
Powertrain & Engine Architecture
The 250 SL was powered by the M129.982 engine, a 2.5-liter inline-six cylinder powerplant. This engine featured a cast iron block and an aluminum cylinder head, employing a single overhead camshaft (SOHC) design. The engine utilized Bosch multi-port fuel injection, a relatively advanced system for the time, contributing to improved fuel efficiency and smoother operation compared to carbureted engines. The engine produced 150 horsepower at 5,500 rpm and 216 Nm (159.31 lb-ft) of torque at 4,200 rpm. Paired with this engine was a four-speed automatic transmission, a popular choice for buyers prioritizing comfort and ease of driving. This automatic transmission, while not offering the driver engagement of a manual, provided a relaxed cruising experience well-suited to the SL’s grand touring intentions.
Driving Characteristics
The 250 SL automatic, while elegant and comfortable, wasn’t known for blistering acceleration. The 0-60 mph time of around 10.1 seconds reflects this. Compared to the manual transmission versions, the automatic slightly diminished performance due to power losses within the torque converter and the transmission itself. However, the automatic provided a smoother, more refined driving experience, particularly in city traffic or on long highway journeys. The gear ratios were optimized for comfortable cruising, with a focus on relaxed acceleration rather than aggressive performance. The steering, utilizing a cone worm and recirculation balls system, was relatively heavy but provided good feedback.
Equipment & Trim Levels
The 250 SL came reasonably well-equipped as standard. Interior appointments included leather upholstery, wood trim on the dashboard and door panels, and a comprehensive instrument cluster. Power steering and power-assisted disc brakes were standard features, enhancing the driving experience. Optional extras included a radio, whitewall tires, and a hardtop in addition to the standard soft top. The interior layout was focused on driver and passenger comfort, with a relatively minimalist design emphasizing quality materials and craftsmanship.
Chassis & Braking
The W113 chassis featured independent suspension all around. The front suspension utilized a double wishbone setup with a transverse stabilizer bar, while the rear employed a trailing arm design. This suspension configuration provided a comfortable ride and good handling characteristics. The 250 SL was equipped with disc brakes on all four wheels, providing ample stopping power for the vehicle’s weight and performance. An anti-lock braking system (ABS) was also available as an option, a relatively advanced feature for the mid-1960s. The chassis was designed to provide a balance between rigidity and weight, contributing to the car’s overall handling and stability.
Market Reception & Comparison
The 250 SL was generally well-received by automotive critics. It was praised for its elegant styling, comfortable ride, and refined interior. However, some critics noted that the automatic transmission diminished the car’s performance potential compared to the manual versions. Compared to the 230 SL it replaced, the 250 SL offered increased power and torque, resulting in improved acceleration and overall drivability. Compared to the later 280 SL, the 250 SL offered a slightly more balanced driving experience, with some preferring its lighter weight and more nimble handling. Fuel economy, at around 21 mpg, was reasonable for the era, but not exceptional.
Legacy
The Mercedes-Benz 250 SL automatic remains a highly sought-after classic car today. The M129 engine, while not the most powerful of its time, is known for its reliability and durability when properly maintained. The automatic transmission, while not a performance enhancer, has proven to be relatively robust. Rust is the primary concern for these vehicles, particularly in areas with harsh winters. Well-maintained examples command high prices in the collector car market, reflecting their enduring appeal and historical significance. The 250 SL represents a pivotal moment in Mercedes-Benz history, bridging the gap between the classic SL roadsters and the more modern grand tourers that followed.
