A saying in the world of art and antiques is “If it was expensive and desirable in period, it will most likely be that way forever.” That’s generally true of the Mercedes-Benz C107 SLC coupes, sold in the United States 1973–1980. Today, these handsome pillarless coupes are desirable, but not that expensive. The SLC is steeped in racing heritage, has fine period style. and is a  very capable grand tourer that can eat up highway miles while delighting occupants. 

It seems that enthusiasts are just starting to appreciate SLCs again for their unique charms. Values that had remained largely flat for years have recently registered an uptick. If this model appeals to you and if you can find a well-preserved original car that’s been well cared for, now is the time to make a move.

It’s hard to imagine that the SLC was actually the replacement for the elegant Mercedes-Benz W111 coupe introduced in the early 1960s, because those were the top-of-the-line S-Class coupes. By the late 1960s, Mercedes-Benz product planners had initial drawings of the replacement for the W113 SL, which would become the much more modern R107 SL. When considering a replacement for the W111, it was decided to base the new coupe on the new SL, as design of that car was much further along than the new W116 S-Class sedan. By simply stretching the new SL, adding a fixed roof and back seat, Mercedes could introduce a new coupe much faster than being forced to wait for the W116 sedan.

Motorsport heritage

After the 1955 Le Mans tragedy, Mercedes withdrew from international motor racing for more than 30 years. However, the firm competed in rallies. In 1978 Mercedes entered several modified 450SLCs in major endurance rallies. The 450SLC won the FIA’s South America Rally, covering over 15,000 kilometers in a 40-day period. Smitten by success, Mercedes-Benz homologated a higher performance SLC, the potent 450SLC 5.0, fitted with a 5.0-liter all-aluminum engine, modified suspension, aluminum body panels and a host of other changes. Mercedes had real rally success with the 5.0. The company then went on to develop the 500SLC, an even more potent weapon. 

The C107 won rallies around the world during the 1978 – 1981 seasons. So, while the performance of the rally developed SLCs is quite different than that of the basic road-going models, the basic DNA is the same. It’s not too much of a stretch to imagine yourself crossing the Andes in an FIA rally while tooling up the gravel driveway to the ‘You-Pick’ apple orchard in your 450SLC. 

Design

The decision to base the new SLC on a modified SL chassis is ultimately what gave the SLC its most prominent, if somewhat controversial feature, the “window louvers” (or “window gills”) located just aft of the rear window and forward of the C-pillar. The 450SLC is the same as the SL from the front bumper to the windscreen, yet the wheelbase is about 14 inches longer than that of the SL (111 inches vs. almost 97 inches). By stretching the car, Mercedes slotted in a reasonably-sized rear seat, but also created a roofline issue if the coupe was to remain pillarless. 

It’s the rear louvers that make the visual transition from the rear side window to C-pillar. They’re a curious design element, and one that’s been much debated at many club gatherings I’ve attended. Some people love them, others don't. Either way, the rear-side view of an SLC is unmistakable thanks to those silver painted plastic louvers sandwiched between two pieces of glass. 

The longer wheelbase improves ride quality, making the SLC a great long-distance tourer: comfortable and solid feeling with the handling of a smaller car. 

Capable performer despite restrictions

The 1970s were tough on performance. Increasingly strict safety and emissions requirements imposed by America's DOT and EPA meant changes to the SLC. The earliest 1973 American market SLCs had attractive, slim bumpers. From 1974 through the end of U.S. production in 1981, SLCs came with larger 5 mph DOT-mandated bumpers. U.S. market 450SLCs used Mercedes’ capable M117 V8; 1973 and 1974 models cranked out 190 horsepower. 

Thanks to increasing emission controls, 1975 – 1979 SLCs made just 180 horsepower. In 1980, power was down to 160 horses, with 0 – 60 times hovering between 10 and 11 seconds, and a top speed of 124 mph. All 450SLCs came with three-speed automatic transmissions. As a result, SLCs can feel a bit “boaty” and cumbersome around town. However, a long-distance highway trip turns into a comfortable and sporty affair behind the wheel of an SLC. The 1981-only 380SLC had a 3.8-liter V8 with 155 horsepower and a 4-speed automatic transmission.

Equipment and options 

As the top model in the lineup, SLCs came well equipped from the factory and had few available options. What was optional and standard changed over the years. For example, standard for 1978 was leather interior (velour available at no charge), metallic paint, air conditioning, automatic antenna, center armrest, Becker Mexico AM/FM w/ cassette, power windows, and cruise control. Options included a power sunroof, orthopedic seatbacks, and heated front seats. Steel wheels with painted wheel covers were standard. Bundt style alloys were available at no charge.

The SLC market

The 450SLC was the most expensive car in the Mercedes range from its launch for 1973 until the 450SEL 6.9 arrived in mid-1977. In 1976, a new 450SLC had a base price of $24,131 delivered to the West Coast, while a 450SEL sedan cost $21,877 and the 450SL was $19,515. By 1980, base SLC prices had ballooned to $42,848, while a 450SL cost $36,130. Despite these higher SLC prices, by the mid-to-late 1980s SLs commanded a premium over the fixed roof SLC.

As time went on, SLC prices bottomed out.  A lot of SLCs fell into the hands of people who might have been able to buy them, but couldn’t afford to maintain them properly. As a result, today there are a lot of very needy SLCs to be found. 

Decent drivers can still be found in the $10,000 range. Nicer cars are pushing $15,000 - $25,000. Great cars range anywhere from about $30,000 - $50,000, but those are really top-quality cars with provable, low odometer readings in excellent, original cosmetic condition. Top prices are for investment grade cars. Still, there are plenty of very nice, driver quality SLCs for well under $20,000. Interesting period-correct colors demand a premium, if you can stomach those seventies shades. I like the funky metallic oranges and greens. I owned a Pastel Blue (color code 922) 1977 450SLC with body colored wheel covers. That car had presence!

Choosing your SLC

I’ve said it before about other vintage Mercedes-Benz vehicles, but it’s  absolutely true about the SLC: find the best one you can, and pay up for a good example. You can’t turn a bad one good without many thousands of dollars and lots and lots of effort. Good cars are out there, you just have to find them. 

What does good mean? Original interiors with dashes that aren’t cracked. Original paint. Cars with limited ownership, or at least known history, plus a thick folder of paperwork showing regular maintenance. Even so, you should budget several thousand dollars of mechanical work to bring the car up to a safe and comfortable standard. Remember, the newest SLC is still a 40 year-old car. With time and patience, you can find just the right SLC for yourself, but don’t delay, the word is out and they aren’t depreciating anymore.