300SL IN TWILIGHT
In the meantime, buyers who wanted a more powerful Mercedes-Benz sports car than the 190SL had another option: the mighty 300SL (W198), the street-going derivative of the Le Mans-winning W194. With its fuel-injected 2,996 cc (183 cu. in.) six, the 300SL had more than twice the power of its 190SL sister, and cost close to twice as much. With the right axle ratio, the 300SL was among the world’s fastest cars, and certainly one of the most attractive.
Handsome as it was, the 300SL was not for everyone. Entry and exit were awkward, ventilation was poor, and the swing-axle rear suspension had unpleasant characteristics at the limit. The roadster, which replaced the coupe in mid-1957, had a better-behaved suspension and conventional doors, but was still complex and finicky for street use.
While Mercedes continued to make functional updates to the 300SL almost until the end of production, there wasn’t much incentive to create a direct successor. The 300SL helped to sustain the luster of past racing victories, but Mercedes had withdrawn from Grand Prix competition in 1955 after the accident at Le Mans that killed works driver Pierre Levegh and dozens of spectators. This left the 300SL as a pretty but aging orphan that was undoubtedly expensive to build and sold in tiny numbers: no more than a few hundred cars a year. From a practical standpoint, a milder, less-expensive six-cylinder sports car seemed a much better bet. However, that project would have to wait its turn.
THE HECKFLOSSE SHEDS ITS FINS
At the Frankfurt Auto Show in the fall of 1959, Mercedes launched the first of its new sedans, the six-cylinder (W111) 220b, 220Sb and 220SEb. All had the 2,195 cc (134 cu. in.) six with between 95 and 120 PS (70 to 88 kW), and all sported stubby tailfins that earned the new models their nickname: Heckflosse, or “fintail.” The fins, a nod to contemporary American styling themes, were omitted from the subsequent two-door coupes, the first of which debuted at the 1961 Geneva show.
The W113 sports car was the last major Heckflosse derivative to be developed. The sports car’s basic engineering “package” was not approved until about four months before the W111 sedans went on sale and full-size clay models were not ready until the summer of 1961, three months after the debut of the 220SE coupe. Production approval followed later that year.
There’s a certain irony in the fact that many of the people responsible for the design of these resolutely Teutonic automobiles were not actually German. Mercedes-Benz chief stylist Friedrich Geiger was originally from Baden-Württemberg, but chief body engineer Karl Wilfert, who had ultimate responsibility for passenger car design, was Viennese, as was Béla Barényi. Designer Paul Bracq, who is typically credited with the W113’s design (along with that of the W111 coupe), was from Bordeaux, while future Mercedes design chief Bruno Sacco, who had joined the design office in Sindelfingen in early 1958 and was involved in the W113’s development, was Italian. Technical director Fritz Nallinger was from Esslingen, but Rudi Uhlenhaut, chief engineer for passenger car development, had been born in London to an English mother.
Nonetheless, the fruit of their labors could hardly have been more Germanic. Where Jaguar’s new E-type was a voluptuous showstopper, the W113 was upright and boxy, almost severe. Paul Bracq’s coupe design was already very clean, but the roadster was a masterpiece of minimalism, stark in a way that only the cheapest or most expensive cars can really pull off. Whether you found it attractively restrained or just bland was a matter of taste, but it looked classy and more grown up than the 190SL, which had always had a vaguely cutesy air.
The Mercedes W113’s cousin and platform-mate, the W111 coupe, seen here in later U.S.-spec 250SE form with the side marker lights mandated by federal safety regulations. The coupe was notably bigger than the roadster, stretching 192.1 inches (4,880 mm) on a 108.3-inch (2,750mm) wheelbase, and was considerably more expensive. (author photo)
Structurally, the W113 roadster had a great deal in common with the Mercedes 220SE coupe and rode a modified version of the same floorpan. The roadster’s wheelbase was shortened from the coupe’s 108.3 inches (2,750 mm) to 94.5 inches (2,400 mm), but the W113 retained the coupe’s 58.5-inch (1,482/1,484mm) tread width. Thanks to the wider track and squared-off fenders, the W113 looked bigger than the 190SL, but that was largely illusory: In fact, the new roadster was only 0.8 inches (20 mm) wider than the four-cylinder SL, although the W113 was 2.7 inches (70 mm) longer overall, probably to allow the installation of the M127 six without the firewall modifications required by the stillborn W127.
Although the W113 was described as a roadster to distinguish it from the 220SE cabriolet, in standard form the sports car was a proper convertible with wind-up windows and a well-padded top that stowed beneath a folding metal tonneau cover. Optional was the W113’s most distinctive and controversial styling feature: the so-called “Pagoda” hardtop. Based on a concept Barényi had developed and patented in the mid-fifties, the hardtop was concave, higher along its outer edges than in the center. The design had some practical advantages, including greater load-bearing strength, but it was none too aerodynamic,and even some Daimler-Benz engineers and executives were dubious about its aesthetics. Chief body engineer Karl Wilfert was not troubled by the love-it-or-hate-it reactions, arguing (correctly) that the Pagoda roof would become a conversation piece and the defining detail of the W113’s design.
The Pagoda hardtop, seen here on a 1970 Mercedes 280SL. The hardtop was fairly tall, with big windows for easier entry and exit and narrow pillars for expansive visibility — a great improvement over the 190SL’s optional hardtop. Unfortunately, the Pagoda roof was heavy (101 lb/46 kg, compared to about 45 lb/20 kg for the 190SL hardtop), which made it very cumbersome to remove. Chrome roof rails were optional on German SLs, but we believe they were standard on U.S. cars. (author photo)
220 to 230
Except for the steering wheel and instrument cluster, the relationship between the W113 roadster and the 220SE coupe was not obvious, but there was considerable kinship under the skin. The roadster’s recirculating ball steering and independent suspension were substantially the same as the coupe’s: a conventional double wishbone layout in front, still lacking ball joints, and suspended with coil springs and an anti-roll bar, and Mercedes’ now-familiar Eingelenkpendelachse system in back, with trailing arms, low-pivot swing axles, coil springs, and an auxiliary transverse coil spring acting as a camber compensator. The main departures from the coupe were 14-inch wheels, radial tires, and a faster steering ratio.
The Mercedes 230SL initially had 5.5Jx14 wheels, changed in 1964 to 6.0Jx14, but all W113s used 185HR14 tires, which were considered fairly racy stuff in 1963; most contemporary radials had section widths in the 155 to 165mm range. Although late 300SL roadsters had four-wheel discs, the 230SL used the same brakes as the 220SE: 10-inch (253mm) Girling discs and 9-inch (230mm) finned ATE aluminum drums with a standard vacuum servo. However, the roadster had a dual-circuit brake system, a safety feature not added to the coupe and cabriolet until months after the W113’s introduction. (author photo)
The W113’s commonality with the W111 coupe had both pros and cons. On the plus side, the roadster’s body was impressively stiff, with a solidity that would embarrass some open cars designed 25 or 30 years later. Like the W111/W112 cars, the W113 also had front and rear crumple zones to protect the occupants in a collision, a very novel feature for a sports car of this period. The roadster’s cabin was also roomy for a close-coupled two-seater; a single transverse rear seat was optional to make the roadster into a 2+1.
The major downside was weight. With its smaller dimensions and aluminum doors, hood, and decklid, the roadster was about 250 lb (115 kg) lighter than the 220SE coupe, but still weighed over 2,900 lb (1,315 kg) with a full tank of fuel — and that didn’t include the 101 lb (46 kg) hardtop. A fully equipped W113 was a good deal heavier than the E-type and only about 100 lb (45 kg) lighter than a Corvette Sting Ray.
The W113’s mass led to last-minute second thoughts about its engine. Originally, it was to share the 220SE’s 2,195 cc (134 cu. in.) six, but Uhlenhaut decided that to be competitive in the marketplace, the sports car needed more than 120 PS (88 kW, 134 bhp). The result was a heavily revised M127.981 engine with a new cylinder head, bigger ports and valves, a higher compression ratio, and a revised camshaft. The block was also revised with an aluminum crankcase and wider cylinder bores, bringing displacement to 2,306 cc (141 cu. in.). Topping this off was the latest Bosch multiport fuel injection system with a separate injector for each cylinder, positioned in the intake port almost directly above the valve.
Like most Mercedes sixes of this vintage, the M127.981 engine had an aluminum head and an iron block, although the 230SL used an alternator instead of a conventional generator, a first for a regular-production German car. The paired tubes leading to the cylinder head are intake runners, designed to provide a resonance supercharging effect at mid-range speeds. (Photo: “M127 right” © 2012 Herranderssvensson; resized 2013 by Aaron Severson and used under a Creative Commons Attribution-ShareAlike 3.0 Unported license)
The result of all this was a healthy increase in power, from 120 PS to 150 PS DIN (110 kW; 170 bhp SAE) at 5,500 rpm. Torque was also increased about 5%, to 144 lb-ft DIN (195 N-m; 159 lb-ft SAE gross) at a rather high 4,500 rpm. Both figures were a dramatic improvement from the 190SL, but still well short of the 300SL’s 225 PS (165 kW; 250 bhp SAE gross).
The larger engine provided the W113’s official name: 230SL, “230” from the engine capacity in deciliters and SL for “Super Leicht” — although calling the 230SL “Light” was probably stretching the point.
Aaron,
Thanks for the mention as a source. Glad I could assist! As a former owner of a 190 Heckflosse, I really enjoyed the write-up!
Keep up the excellent work!
EB
Thanks for another good read.
In the second paragraph of the 250SL section is this line:
“…combined the 82mm (3.23-inch) stroke of the 230SL’s six with a longer 78.8mm (3.10-inch) stroke for a total displacement of 2,496 cc (152 cu. in.).”
You’ve got two numbers listed as the stroke. Am I correct in guessing the 82mm number is the bore of the engine?
Oops! Yes, that should have been "the 82mm (3.23-inch) bore."
Thanks for the correction — I’ve amended the text.
Thorough and judicious as always, you capture perfectly the virtues and drawbacks of the113 with a fine sense of historical context and the competition.
I may be wrong, but I believe the dark blue 230SL you show has replacement US headlight frames from a 280, with the much larger orange turn signal lens, instead of the narrow orange strip at the bottom–a not uncommon thing to see, as are replacement tail lights with orange blinkers, instead of the full red lenses. Not nit-picking here–in the eternal restorers’ debate between aesthetics and accuracy, I am an aesthete. I have a 67 pseudo-250SL: originally a 230 (as VIN indicates), but a replacement block from previous owner from a 250SE. He also put on a 250SL trunk badge, which is one of many hard-to-find-so-absurdly-expensive parts for 113’s. I’ve further mucked it up for purists by installing European headlight units on an originally US car, but they express the clean original Bracq design much better to my mind.
Market values for the 250SL (real, not pseudo, like mine) remain oddly less than one would think, given their short production run, and what at least some consider its combination of superior power to the 230 and lighter weight and less squishy suspension than the 280. The latter seems to have been modified with more of an eye to the US market, particularly in the increasing prevalence of automatics over manual gearboxes. With the 107 firmly aimed at American tastes, the manual all but vanished from US-spec models, and Mercedes certainly cashed in. There’s an interesting (arguably saddening) history to be written about the evolution of Mercedes in response to the US market, from the 70s to the present, as they’ve recalculated designs according to customer tastes, changing technology, and (perhaps most dramatically) the rise of Lexus in the 90s.
For all the drawbacks of the long throws, the engine noise from gearing ratios at high speed, and so forth–about which you’re spot-on–the manual in my 113 is so much fun to drive, and the exhaust note is wonderful (the sound of engineering, not “sound engineers” fiddling with the muffler or (laughably, to me) electronic tweaks to the stereo system, as in some new sports cars. The 113 as a whole can be a money-pit far beyond the 107, given the complexity of welded body work around the grill, hood, and fenders (none bolted on, as with 107’s); aluminum hood, trunk lid, doors, and use of metal instead of plastic in so many places (grill screen, dash, door sills, and on and on); complex, difficult-to-fit wood and other trim on the dash; literally countless grease fittings (and I do mean “literally” in the dictionary sense; even experts on SL forums seem to discover new ones); and antiquated rust-proofing on a body that seems designed to collect water rather than drain it in certain spots. The mechanical fuel injection needs adjustment beyond the skills of all but specialists, including MB dealers, and front-end body work is both expensive and, unless very well executed, will give itself away immediately in panel gaps around that lovely hood design. A 107 is a much saner and cheaper collector choice. But with a fairly well-sorted solid “driver,” by no means fully restored, I’ve never regretted getting my 113, which feels like a machine, not an appliance, yet is utterly easy to drive and rides better than many cars designed decades later. And the shape and proportions are to my eye almost perfect; next to it, the far-more-modern 107 sacrifices character for sleekness. In Dallas, I get happy waves from people who would never notice a 107 (which are all over the place) or a late-model SL that cost 5x what mine did to buy.
Apologies for self-indulgent response. And thanks again for your work!
Thanks, Rick! I think you’re right about the lights and have amended the caption. I was so distracted dealing with the paste-up (typing HTML img tags by hand — don’t ask) that I missed that.
I would be very curious to know how many European W113s of each generation had automatic. Based on the comparative U.S. and rest-of-world production figures and the various estimates I’ve seen for the percentage of cars with automatic, it can’t have only been American buyers opting for it. Still, the fact that the U.S. R107 was offered only with automatic is noteworthy.
For better or worse, the R107 is still too ubiquitous to really stand out. In this part of Los Angeles, it’s hard to go outside without seeing one and the longevity of the design means that it registers as an older car rather than an Old Car. (The C107 is considerably less common.)
On the fuel injection system, I suppose it’s only fair to point out that most mechanical injection systems of that time were similarly intolerant of shade-tree mechanics. On Triumph’s 2.5 PI engine, for instance, the factory service manual included stern warnings not to even try adjusting or resetting the metering unit’s diaphragm springs, which required very fine tolerances.
One would assume that since the R107 was offered only with automatic in the U.S., a majority of American W113 owners had ordered automatic. But there’s another wrinkle, which Road & Track mentioned in their first road test of the R107. Smog-certifying both manual and automatic R107’s for the U.S. would have been that much more expensive. Road & Track gave a figure (which I no longer remember) for the percentage of W113’s sold with automatic in the U.S. and said Daimler-Benz “had to go with the majority.”
As an indication of one demographic to which the W113 appealed, I read an article around the time the BMW 325 Cabriolet was introduced. The writer said that until the advent of the 325 Cabriolet, the W113 was really the only game in town for doctors’ wives.
To my eye the boxy look is fine on M-B sedans but not on the R107. The W113 is so much more graceful.
The separate emissions certification cost is a major reason why we no longer get a lot of cars with manual transmission even if they’re sold that way in other markets — or if we do, the manual actually costs more than the automatic. (That said, it’s interesting to note that some Japanese cars have been sold here with manual transmissions that weren’t offered in the home market.) In any case, the newer three-speed torque converter transmission was probably better suited to U.S. driving styles anyway, particularly with a V-8 engine.
I have a feeling the R107 was intended to look more “masculine.” I don’t recall offhand if the designers specifically said that (although they were certainly conscious that it was bigger and bulkier than the W113), but it would make sense from the results. I don’t know how the demographics of the R107 differed from those of the W113 overall, but at least in L.A., it seems the R107 had a fairly unisex appeal.
I think perceptions of the R107 end up being skewed somewhat by the model’s longevity. Its lifespan overlapped several generations of Mercedes-Benz sedans, each of which became progressively sleeker while the roadster stayed (at least visually) the same. Not that the R107 isn’t objectively bulkier and less graceful than the W113, but having viewed it against cars of the late ’80s as well as the ’70s, the effect is exaggerated.
This was a fascinating and quite comprehensive read. At the last Frankfurt Auto Show and more recently the Essen Techno Classica there were many W113s present. It is apparent their values are increasing, unlike the not particularly liked successor. A number of specialists here in Germany have taken to building cars that retain the 230-280SL styling but with modern Mercedes-Benz engines and transmissions. At an impressive price, of course!
i learned to drive on my dad’s ’71 280sl. only negatives were the automatic, 4.08 rear end (felt bad taking her on the interstate), heavy a/c that was never used, and the points constantly frying up.
love to do a resto-mod if the car would still sound the same. amazing exhaust note. perfect car for going to the golf course.
Thank you for this article. As I’ve only just discovered this website, I am very impressed with the thoroughness and depth that make this article a true gem. Very inspiring.
My grandmother bought a ’72 250C brand new, she kept it for 25 years, and I drove it a lot over that time. The comments on the Mercedes automatic transmission are so spot-on. If you drove it with just the right amount of partial throttle it shifted almost smoothly, anything else and it was jerking and slamming gears. Boy, I miss that car.
Did any of the early 1964 230 SL come with dual carbs instead of Bosch fuel injection.
Not from the factory, but since there were dual-carburetor versions of the 220 and 250 engines in the sedans, it seems entirely possible that someone might have done a swap for some reason.
Owner of 1970 250C …..motor swapped on 76′ to a 280 S/A…..yes yes stamped on the head is S/A ….definitely not a 8 ….block says 130 923 12 001641 …does anyone know this model ? Closest I could come was a 280S a/c or the 280 S/8
The Triumph Stag was aimed at more or less the same market segment as the W113 and R107. Unfortunately for the Stag, it was developed and introduced at a time of extreme dysfunction at British Leyland. It quickly acquired (and never really lost) a reputation for poor build quality and engine problems.
Thanks for that fine article. I recently purchased a 1963 MB 230SL
standard transmission. The car seems to be treated poorly at sometime during it’s past. The steering wheel cracked, the top of the ashtray is missing, but it is a fun car to drive, I am slowly bringing it back to good form. BTW, any idea where I can get a top to the ashtray? I fear that I might have to get it fabricated.
I’m afraid I can’t help with parts or repairs, sorry!
The Stag was a later car than the W113, and was an occasional 4 seater. Its main competitor , on the UK market a least , was the Reliant Scimitar GTC
All true. On the other hand, the W113 was one of the key inspirations for the Stag (whose development was quite protracted) and Triumph explicitly hoped to make the Stag that kind of car. Obviously, the Mercedes was a lot more expensive (and the R107 350SL was even more so), and Triumph didn’t have that kind of cachet, but that’s the sort of buyer they wanted to court.
Of course, it didn’t turn out that way, but massive disparities between intention and outcome are a central theme of the Stag story…!
Rather intrigued by the 115-134 hp 2.2-litre output of the M127 engine in the Mercedes-Benz W127 prototype, both it not being produced with neither it or the Mercedes-Benz W121 featuring a coupe bodystyle were missed opportunities.
Quite perplexed by the outputs of the M180 6-cylinder engine as find it difficult seeing capable of putting out 110 hp whereas the M127 was comfortably able to exceed those figures, also interested to know the M180 family’s relation to the larger M186 family.
The issue was pretty plainly torque, and in particular the shape of the torque curve. Torque output with normally aspirated engines is directly related to displacement. Many of the changes that will provide more horsepower from a given displacement either won’t produce a commensurate increase in torque. Some will actually hurt torque output or at least alter the torque curve in undesirable ways. The M127’s torque peak was 4,500 rpm, which was quite high for the time and forced some awkward compromises in gearing to compensate. In the heavier sedans and coupes, that would have been even worse.
It’s easy to lose sight of that issue when one becomes accustomed to modern engines, which are vastly more flexible. With modern engines, especially with forced induction, the torque peak doesn’t tell you much about the shape of the curve, whereas with early sixties technology, a torque peak above 4,000 rpm was likely to mean a very peaky, high-strung engine.
Can understand as way variations on the M180 were still used to some extent instead of the M127, just brings up the question of whether even further could have been extracted from the M180.
Like the idea of the Mercedes 190SL W121 receiving an 110 hp M180 or 115-134 hp M127 in W127 prototype form as a German equivalent to the Big Healey, which also switched from 4-cylinder to 6-cylinder engines.
Despite the potential compromises in refinement and tractability, is it known how much more power was capable of being extracted from the 105 hp 1.9-2.0 M121 4-cylinder engine or what it would have likely entailed?
I don’t have any details regarding what Nallinger tried in getting more power from the M121, but in that era, the steps involved in getting more power out of a given engine of given duration were generally straightforward: bigger ports, bigger valves, greater valve lift, longer duration, more carburetion. Not all of those are necessarily practical; for example, existing cylinder head design may impose limits on port size and shape, or oil system design may be inadequate for sustained high-rpm use. This makes your question more complicated than it might appear because some modifications may have required extensive and expensive design changes, such as new cylinder heads, for very modest improvements in power and significant cost to low-speed response.
The Big Healey is potentially a misleading comparison because the switch from the big four to the six was initially a matter of production economy rather than a product planning decision; the initial 100-6 lost some ground in performance. (It’s also significant there that the 2.6-liter C-series six was actually about 21 cc smaller than the big four!)
Read the M121 later M115 4-cylinder and the M180 family up to the M110 6-cylinder were related to each other (along with the dieselized 4/5-cylinder units), given the M121 and M180 engines shared history (and other related derivatives) it is strange the 6-cylinder was not capable of reaching 3-litres+.
In theory an 1897cc/1988cc 4-cylinder M121/M115 of similar spec to the 134 hp 2196cc M123 or 168 hp 2778cc M130 have a potential output of 115-116 hp (1897cc) and 120-121 hp (1988cc) for an alternate 190SL W121. Meanwhile using the much later 182 hp 2749cc M110 Twin-Cam as a rough guide equates to a potential 1988cc 4-cylinder output of 132 hp.
Brought up the Big Healey comparison because it immediately comes to mind even if the background for it differed from the W121 and W127 prototype.
I can’t claim to be sufficiently familiar with the fine details of Mercedes engines to tell you how closely their four- and six-cylinder engines of this vintage relate to one another. However, comparing specific outputs the way you’re doing is potentially misleading. A six-cylinder engine has a number of intrinsic advantages, including in breathing, and if the engines are part of the same family, the six will also have greater displacement and thus more torque. Even for engines of identical displacement, the four will need significantly bigger valves to match the total valve area of the six, which the standard port design might not easily accommodate, and would need greater valve lift and longer duration to compensate, hurting low-end response.
My suspicion — which again I’m not familiar enough with the engine development saga to confirm — is that porting ended up being a limiting factor for the M121. Small ports have advantages; they tend to give better low-end torque because you have greater intake velocity at low rpm, and they allow the head to be physically smaller. They obviously become a bottleneck when it comes to extracting more power, but if you have a closely related small-displacement six, that may not seem like a significant problem. However, if you want to get more power out of the four, the port design may leave you boxed in, wrestling with questions like whether it’s worth the cost to completely redesign the head for a gain of a few horsepower.
As for the displacement, I don’t think that one should assume an engine not being expanded beyond a particular threshold meant that it wasn’t capable of being expanded that far. The 2.8-liter threshold was a pretty hard limit in terms of taxation in some markets, like France, and Mercedes-Benz wasn’t yet centering the U.S. market in their product planning decisions. They may well have said, “We’ve already got a 3-liter engine for the few applications that need it,” and left it at that.