Reviewed by Unique Cars and Parts
Our Rating: 3
Introduced early in 1971, this impressive two-seater sports car replaced the 280SL. The body and chassis of the 3rd generation SL was considerably heavier and longer than its predecessor, but still showed a slight resemblence to them.
The front and rear axles were similar to those of the 200-250 models, with independant wheel suspension
using double wishbones and anti-drive control at the front and a diagnol swing axle at the rear. A four speed fluid-coupling automatic transmission
was available as an option. The 3.5 litre V-8 engine underwent slight modifications to those being used on other models and the gear shift lever was placed on the floor.
The standard transmission
provided a top speed of 210 km/h and a very respectable 0-100 km/h in 8.8 seconds. As with the previous generation SL's, the vehicle came as an open roadster with removable hard top pagoda roof. More stringent emission controls soon dictated that the engine be increased in capacity to 4.5 litres, however this larger displacement engine used 10% more fuel for an identical horsepower rating, making the earlier 350 engined cars the pick of the bunch.
The R107 body shape went on to become one of the longest running styles from Mercedes, remaining in production until 1989 with some 13 variants durin that time. Even by today's standards for sports cars the 350SL's spacious cockpit looks excellent and may feature beautiful real Zebrano ("zebra") wood accents as a factory option, combined with leather upholstery.
In fact the only disappointment with the interior is the size of the steering
wheel, large by the standards of the day it is the only item on the vehicle that could be considered "too oldfashioned". If purchasing or restoring a classic SL, colour choice is very important. Naturally you cannot go wrong with red, but Astral Silver over black is an equally worthy choice - for these are Mercedes' classic racing colors dating back to the 1930s.
Astal Silver (DB paint code 735 ) can be found on all of the legendary Silver Arrows of Caracciola and Nuvolari
fame as well as on the Mercedes streamliner that broke the world land speed record when driving 268mph on the Autobahn.
Impressions Of The R107 At Release
Whenever Mercedes-Benz presented an all new model, it generally incorporated a number of advanced technical features. The 350 SL was no exception. It heralded a new departure in sports cars in that the primary emphasis was placed more on comfort and safety-features which, inherently, made a car heavier - than on classic design for light weight and handling. It was obvious even to the casual observer that the 350 SL wasn't competition oriented, but traffic oriented. And as such, it left little to be desired. On a long trip it possessed all the attributes of a then modern GT car: comfort, relative silence, a good ride, adequate luggage capacity for two and, most important of all, it required very little driving effort to cover ground rapidly.
The front- and rear suspension
components of the 200/250 Series saloons were employed, putting an end to the low-pivot swing axle which has been utilised for so many years in the Mercedes sports cars. With the 350SL the rear wheels were suspended on diagonal, lower arms with coil springs having cooaxially located dampers. The aluminium, 3.5-litre V8 engine was a scaled-down version of the big, 6.3-litre Mercedes unit and was identical to that powering the 280 SE/SEL 3.5 and 300 SEL 3.5 saloons.
It delivered 200 (DIN) bhp @ 5800 rpm and possessed a single overhead camshaft for each bank of cylinders and Bosch indirect electronic fuel injection. Very smooth in operation, it had a good reserve of both power and torque throughout most of its operating range. Either a manual, 4-speed transsmission or the Mercedes-Benz 4-speed automatic unit with torque converter and planetary gears could be specified.
It was in the area of body construction, however, where the greatest advances had been made. Karl Wilfert, one of the world's leading authorities on autoomotive safety led the design team responsible for the 350 SL's body. Of unitised construction, it was delivered with a cloth, convertible top and the "pagoda
"-type, removable hard-top could be ordered as an option, just as on the previous 230/250/280 SL types. Whereas these cars had aluminium doors, those of the 350 SL were steel, in compliance with the U.S. safety norms.
Much use was made of the ElastoElement-Methode (ESEM), developed jointly by Mercedes-Benz and Teldix. This system employed a computer to analyse each component relative to the total strength of the entire body unit. It was possible to increase windshield post strength by 50 per cent. The posts were also designed so that rain water was deflected upwards, over the top, rather than against the side windows. An advanced ventilation system directed air against these to keep them clear. The corrugations on the lower body sides also tended to keep the windows free from mud and water splashed upwards from the road, the wrap-around tail lights being specially designed to remain clean under adverse conditions. Halogen headlamps were standard equippment and, in those countries which permitted its use, a halogen rear fog warning lamp was employed.
Recirculating-ball-type power steering
was standard and the 4-spoke steering
wheel was of new design to reduce impact, combined with the previously employed Mercedes-Benz padded wheel centre. The side mirror could be adjusted from the inside and was constructed to snap off under impact. Large, round, whiteblack instruments were clustered directly in front of the driver to supply instant, legible information. Ergonomically, the interior was well thought out, enhancing the ease with which the 350 SL could be driven. Though a 2-seater, a small rear seat for children could be specified as an option.
With a top-speed capability of 130 mph and a zero-to-60 time of under 9 seconds, the brake system had to match the 350 SL's performance potential, being of the dual-circuit type, power assisted with discs all round, the front pair ventilated. The newly introduced, electronic Anti-Bloc unit, which could intermittently apply each brake individually for optimum retardation under all road and climatic condiitions, was available for the first time, as an option.
In keeping with all the safety features, the steering
box was located behind the front-wheel centres and the column was designed to collapse on impact. The fuel tank was positioned above the rear-wheel centres, behind the passenger compartment and to the front of the luggage boot, thus moving it out of the danger zone in a rear-end collision. Door hanndles were newly designed to be pulled, and the rear window of the optional hard-top was electrically heated on some.
The U.S. version of the 350 SL used a 4.5-litre engine coupled to a 3-speed automatic transmission
, the larger-displacment powerplant being able to more easily comply with the strict emisssions standards. The impression you had when viewing the 350SL from the outside was that of a rugged, sturdy construction, the smooth, ripple-free sheet metal and fine finish in the best of Mercedes tradition enhancing this feelling. Entry and exit were comfortable and the seat backs were adjustable for rake. Visibility was excellent and the cockpit was very roomy, but it was a little surprising to see such a large steering
wheel considering there was power assistance.
The fuel injection
engine idled very smoothly and power came on instantly, which was also due to the single overhead camshafts. Both the manual and automatic transmissions
were well matched to the engine's potential, the automatic unit shifting very smoothly. The basic tendency was that of oversteering, but there was never the feeling of having to force the car into a corner, the steering
effort being low. All in all, it was an excellent road car for rapid journeys.
The Perfect Sports Car For The 1970's
However, it was in town driving and dense-traffic conditions where it becom evident, especially with an automatic transmission
-equipped 350 SL, how radically the term "sports car" has changed in the eyes of the Mercedes-Benz engineering department. The SL had metamorphosed from the 300 SL of the early Fifties - a hard sprung, competition-oriented machine based directly on the 300 SLR racing sports car - to a comfortable tourer which didn't require much effort to make it go fast; it was, as a matter of fact, a rather sedate machine in comparison to the driver's-car nature of the 300 SL, which required effort to negotiate the road rapidly and great skill to control at high speeds. It was, however, one of the fastest road cars of its era.
The 350 SL was just another good GT automobile
; safe, simple to drive and not requiring any great skill, very comfortable and, despite all the advanced design features, not in the least bit an exciting car. A sports car for the Seventies had different functions to fulfill than one from the Fifties. It had to meet rigorous safety and emissions standards for th U.S. market; it also had to cope with increasingly dense traffic conditions in Western Europe. The 350 SL did all these things very well because that is what it was designed for. In this respect it was the perfect sports car for the 1970s.
Solid and impressive, the styling of the 350 SL appeared to be slightly heavy handed with the "pagoda" top in place. The car had better-balanced lines in open form with its top down.
Mercedes-Benz 350SL Quick Specs
Chassis and suspension:
- Unitised construction with fully independent suspension.
- Front, upper and lower wishbones, coil springs with concentric dampers, progressive-acting, auxiliary, rubber buffers, stabiliser bar.
- Rear, diagonal, lower arms, coil springs with concentric dampers, progressive-acting, auxiliary, rubber buffers, stabiliser bar. Four-wheel disc brakes, front discs ventilated, dual-circuit, servo-assisted system. Recircuulating-ball power steering.
- Wheelbase 8 ft. 0.8 in.
- Track, front 4 ft. 9 in., rear 4 ft. 8.6 in.
- Length 14 ft. 4 in.
- Width 5 ft. 10.4 in.
- Height 4, ft. 3.1 in.
- Ground clearance 6.29 in.
- Turning circle 33 ft. 9 in.
- Unladen weight 3399 lb.
- Fuel tank capacity 19.7 gallons (Imp.)/23.7 gallons (U.S.)
- Tyres 205/70 VR 14 radial ply Dunlop SP or Michelin X
- Aluminium, sohc V8
- Bore 92.0 mm. Stroke 65.8 mm
- Cubic capacity 3499 cc
- Compression ratio 9.5:1
- Bosch indirect electronic fuel injection
- Power output 200 (DIN) bhp at 5800 rpm
- Max. torque 211.2 (DIN) lb.-ft. at 4000 rpm
- Front engine, rear drive
- Four-speed, all sychromesh, manual: 13.70, 8.09, 4.95, 3.46. Reverse 12.87. Final drive: 3.46
- Optional four-speed automatic transmission: 13.77, 8.26, 5.05, 3.46. Reverse 18.96. Final drive: 3.46
- Top gear per 1000 rpm 21 mph
- Optional, limited-slip differential