When you think of Mercedes-Benz and rallying, certain iconic models might spring to mind. Perhaps the formidable 300SL W198 or the elegant 230SL W113, both of which saw factory-supported racing activities. These are the celebrated stories, the well-documented chapters in Mercedes-Benz’s rally history. But what about the lesser-known tales, the projects that almost were? The story of the Mercedes-Benz R107 500SL rally car is one such intriguing near-miss, a fascinating episode of what could have been.
Yes, you read that right – a Mercedes-Benz R107 500SL rally car. It existed, it was developed, but it never officially competed. Before you get completely lost in confusion, let’s rewind to the late 1970s when Daimler-Benz, under the direction of Erich Waxenberger, was actively participating in the World Rally Championship. Their weapon of choice in 1978 and 1979 for Group 4 events was the robust 450SLC 5.0 C107.
In 1980, the 450SLC underwent a subtle transformation, gaining black wheel arch extensions and a new designation: 500SLC. This updated model was deployed for Group 2 rally events in demanding locations like Argentina, New Zealand, and the grueling African Bandama Rally. Initially producing 305 horsepower, later boosted to 329 hp, the 500SLC, despite its power, faced a fundamental challenge: its sheer size and weight. This grand coupe, while capable, was proving to be cumbersome for the agility demanded by rally courses. A lighter, more nimble alternative was clearly needed if Mercedes-Benz was to truly compete for rally supremacy.
Developing the Mercedes-Benz 500SL Rally for Group B
The answer, conceived for the 1981 World Rally Series, was the Mercedes-Benz R107 500SL Rally. Erich Waxenberger, the driving force behind Mercedes-Benz’s rally efforts, spearheaded the project to transform the luxurious 500SL roadster into a competitive rally machine. To shed crucial weight, Waxenberger’s team implemented a series of strategic modifications. An aluminum roll cage was installed, providing essential safety and structural rigidity while significantly reducing weight compared to a steel cage. Furthermore, some of the standard steel chassis panels were replaced with thinner gauge steel, typically found in Mercedes-Benz sedans, further contributing to weight savings. The roof, rather than being welded, was bolted onto the chassis with seven screws, another weight-conscious decision aimed at facilitating quicker removal and maintenance during rally events. Except for the windshield, all glass areas were replaced with lightweight polycarbonate, a shatter-resistant plastic material ideal for the rigors of rallying.
The windshield, bonded to the frame and crucial for the car’s overall structural integrity, remained in glass. Inside, the transformation continued with a focus on functionality and weight reduction. Heavy, plush seats were swapped for lightweight Recaro plastic racing seats, each weighing a mere 4 kilograms. These modifications collectively resulted in a substantial weight reduction. The new Mercedes-Benz R107 rally car tipped the scales at a svelte 1,350 kg (2,976 lbs), a remarkable 236 kg (520 lbs) lighter than the 500SLC coupe it was intended to replace.
While some online sources and publications have speculated about the 500SL rally car boasting outputs of 340 hp or even 380 hp, official Daimler-Benz documentation does not support these claims. However, the rally-prepped 500SL did feature a notable novelty: a four-speed automatic transmission that could be manually shifted, offering the driver greater control in demanding rally conditions. For optimal performance in rally stages where top speed was less critical than acceleration and responsiveness, the car was fitted with a shorter final drive ratio of 1:4.08. This modification contributed to an impressive 0 to 100 km/h sprint time of just 5.9 seconds, while still allowing for a respectable top speed of 220 km/h.
Walter Röhrl: Taming the 500SL Rally Beast
With four meticulously prepared Mercedes-Benz R107 500SL rally cars ready to go, the critical missing piece was an experienced driver capable of harnessing the machine’s potential. The car was initially deployed as a test vehicle at the 1980 Bandama Rally, providing valuable data and insights. Enter Walter Röhrl, a Bavarian rally ace who had just clinched the 1980 World Rally Championship title for Fiat, driving a 131 Abarth alongside co-driver Christian Geistdörfer.
Secured with a ten-year contract, Röhrl immediately commenced testing the 500SL to evaluate its capabilities for a potential 1981 World Rally Championship campaign with Daimler-Benz. Compared to the agile Abarth Fiat, the Mercedes-Benz R107 rally car presented a different driving experience. It was significantly heavier and audibly louder. Equipped with a limited-slip differential boasting an 80% locking rate and a revised parking brake featuring an upright lever, the 500SL was not just about raw speed. It was also capable of captivating spectators with spectacular drifts, a driving technique often necessitated by the car’s inherent handling characteristics. The powerful V8 engine, while providing ample power, contributed to a front-heavy weight distribution. This meant that drivers like Röhrl had to master the art of “swinging” the car around before corner entry to counteract the tendency for understeer, ensuring the car turned effectively regardless of the front wheels’ direction. Walter Röhrl, renowned for his car control and adaptability, was considered the ideal driver to manage these unique handling traits. Interestingly, Mercedes-Benz engineers were already exploring solutions to mitigate the front-heavy nature of the car, even sketching concepts for a potential mid-engine conversion, demonstrating their commitment to optimizing the 500SL’s rally performance.
Project Cancellation: A Rally Dream Dashed
In December 1980, Erich Waxenberger returned from the Bandama Rally triumphant, his 500SLCs having secured a dominant 1st and 2nd place finish. However, this victory was overshadowed by an impending board meeting that would decide the fate of the 1981 rally season funding, and with it, the future of the Mercedes-Benz rally program. Waxenberger, invited to present his case, boldly promised to deliver the World Rally Championship title to Daimler-Benz by 1986, coinciding with the 100th anniversary of the automobile, a fitting tribute to Mercedes-Benz’s pioneering legacy.
However, a seemingly innocuous question posed prior to this crucial meeting would inadvertently derail Waxenberger’s ambitious plans. A board member, harboring some skepticism, inquired of Walter Röhrl whether it would be possible to not win the prestigious Monte Carlo Rally in January 1981. Neither Röhrl nor Waxenberger intended to immediately dominate the rally circuit with the new 500SL, recognizing the need for development and refinement. In a moment of candor, Röhrl cautiously replied that he anticipated a top-five finish at Monte Carlo.
This honest assessment, relayed back to the board, had unintended consequences. The board, perhaps misinterpreting Röhrl’s realistic expectations as a lack of confidence, grew wary of Waxenberger’s bold championship promise. After considerable deliberation, they ultimately decided to scale back their rally program, approving funding for only a single car entry instead of the planned two.
Waxenberger’s Gamble and the Unforeseen Fallout
This reduced funding was a significant blow to Waxenberger’s rally aspirations. He had prepared four cars and secured two world-class drivers in Walter Röhrl and Ari Vatanen. In a move that backfired spectacularly, Waxenberger, in a moment of frustration and perhaps misjudging the board’s resolve, declared that if he couldn’t secure funding for two cars, he would rather abandon the entire rally program. With that dramatic statement, he reportedly stood up and left the meeting, expecting the board to concede and recall him, much like he had heard corporate design head Karl Wilfert had done successfully in the past to get projects approved, including the iconic W113 “pagoda” roof.
However, Waxenberger’s gamble failed to pay off. Unlike Wilfert, who carefully cultivated support among board members before making such bold moves, Waxenberger lacked key allies on the board. His ultimatum was met with silence. The board did not yield. The case was closed. The Mercedes-Benz R107 500SL rally project was abruptly cancelled. Reigning World Rally Champion Walter Röhrl, co-driver Christian Geistdörfer, and their Finnish teammate Ari Vatanen were suddenly without a rally team, a harsh pre-Christmas blow.
The abrupt cancellation, while seemingly triggered by Röhrl’s cautious Monte Carlo prediction and Waxenberger’s ill-fated threat, likely stemmed from deeper underlying factors. Rumors circulated that Daimler-Benz’s rally budget, even for a limited program utilizing the SLC and 280E W123, rivaled the entire season budgets of other manufacturers. Mercedes-Benz cars were enjoying strong sales at the time, with long customer waiting lists. The rationale emerged that investing heavily in a rally program that offered no guaranteed victory was financially imprudent. There were concerns that a less-than-stellar rally performance could tarnish Mercedes-Benz’s prestigious image and negatively impact overall sales. In an era where Mercedes-Benz was perceived as vastly superior to competitors like Fiat and Opel in the public eye, the prospect of being outperformed in rallies by these brands was deemed unacceptable and potentially damaging to the brand’s “super image.” The headlines proclaiming “Fiat and Opel Better Than Mercedes” were a public relations nightmare Mercedes-Benz was keen to avoid.
The Rally Spirit Endures
While Daimler-Benz’s official withdrawal marked the end of the Mercedes-Benz R107 500SL’s journey as a factory-backed rally car, it wasn’t the end of the story altogether. The existing cars and a stockpile of spare parts remained. Enthusiasts and privateers, recognizing the potential of the 500SL rally cars, were eager to acquire them and demonstrate their rally capabilities, even with limited resources. Instead of being scrapped, as was common practice for abandoned projects in the motorsport world, the Mercedes-Benz R107 500SL rally cars were given a second chance.
If you’re intrigued to discover how this captivating story unfolds and learn about the fate of the original cars, you can find more details in my book and e-book about the R107 and C107 Mercedes-Benz models: R107 book and e-book. This comprehensive resource covers the complete history of both the R107 and C107, including a detailed buyer’s guide, chassis number explanations, and data card information. The provided link directs you to the US Amazon site, but the books are available on other country-specific Amazon sites under the same title.
Finally, a word of caution: should you encounter a silver Mercedes-Benz R107 500SL Rally car officially displayed at a Mercedes-Benz event or participating in vintage rallies, be aware that it’s likely a meticulously crafted replica and not one of the original, almost-forgotten rally machines.
