Swiss Shadow - 1981 Sauber BMW M1R Group 5

In 1976, the Federation Internationale de l'Automobile introduced a brand new category to draw renewed attention to the world of endurance racing. Motorsport as a whole had been ravaged by the effects of the 1973 Arab Oil Embargo, which had put a heavy emphasis on saving fuel, making racing seem like a frivolous and wasteful pastime in the public eye.

The financial strain and bad public image resulting from this cause grid numbers to shrink drastically, as smaller teams were unable to keep going and large manufacturers were unwilling to. With the new Group 5 category, the FIA hoped to recapture the excitement which had made the sport popular in the easiest and most affordable way possible.

Group 5 brought in big power, big wings and big flames.

The idea behind the class was beautifully simple. Firstly, the governing body ensure a large backing for the class by making any car already homologated in Groups 1 through 4 would be eligible for use in Group 5. This gave both major manufacturers and smaller private teams easy access.

Secondly, there would be almost no restrictions to speak of. Of the homologated cars, only select body panels would actually have to be used, including the roof, bonnet, doors and the rail panel. Otherwise, every bit of the car was open to interpretation, leaving room for impossibly wide tires and enormous wheel arch extensions and wings.

Even in Turbo form the 320i wasn't able to vanquish the 935 juggernaut.

One manufacturer enticed by the new formula was BMW, which had recently launched its BMW Motorsport division. Though the company found the easy way in by modifying their existing 320i touring car to Group 5 specifications, the Germans wanted to do much more.

In order to properly launch their Motorsport brand, they felt the need to produce a halo car. This vehicle was supposed to be much faster than the 320i, enabling it to take the fight to bitter rivals Porsche, who had hit the ground running with their 935.

This design brief called for a mid-engined layout, something BMW had very little experience with. Because of this, Italian chassis specialist Gianpaolo Dallara was called in to design the M1's tube frame chassis. BMW's biggest contribution was the M88 3.5L straight six, which was derived from the M48 used in the famous 3.5 CSL. Exterior styling was handled by skilled Italian designer Giorgetto Giugiaro, who reused key elements from 1972's BMW Turbo Concept.

1972's BMW Turbo Concept inspired the M1.

Because BMW felt their engineers lacked the expertise to produce a mid-engined vehicle, the firm brokered a deal with Italian sportscar moguls Lamborghini to construct both the prototypes and production models from 1978 onward.

However, Lamborghini was on its last legs at the time, and had actually been saved from the cold embrace of death by accepting the BMW deal. Though the deal enabled them to keep the factory going for a while longer, it didn't exactly help them set up a stable development process for the M1.

Sensing the imminent collapse, BMW tore up the contract and regained full control of the M1 project after only seven prototypes had been completed. As the design still hadn't been finalized, BMW was approached by Italengineering, founded by a group of former Lamborghini employees, who finally completed the chassis.

The myriad of issues leading up to production meant BMW missed their window to take the fight to Porsche. Since the car didn't enjoy prior homologation in Groups 1 through 4, BMW needed to produce at least 400 cars to qualify for Group 4, which would then lead to automatic Group 5 entry.The homologation requirement proved to be a thorn in BMW's side, as the hand built cars took ages to produce in-house.

The M1 Procar Championship was a brilliant bit of damage control.

With no real prospect of completing and selling the required number of cars in the foreseeable future, the Jochen Neerpasch invoked a contingency plan. In order to make the M1 the publicity magnet it was always meant to be, the BMW M1 Procar Championship was founded.

This series featured modified M1's akin to their potential Group 4 spec, was run in support of eight European rounds of the Formula One World Championship, and pitted noted GT and sportscar drivers against selected drivers straight from the current F1 grid, like Nelson Piquet and Niki Lauda. Contested over the 1979 and 1980 seasons, Procar was an immense success, giving some justification for the nightmarish project.

The Group 4 version finally appeared in 1981.

BMW finally reached 400 cars in 1981, three years after the start of the project. Even though the M1 had raced at Le Mans under IMSA regulations since 1979, its approval by the FIA finally opened the floodgates for a diverse group of teams to start running modified them in European competition.

This was helped by the cancellation of the Procar Championship the same year, as BMW decided to focus on its Formula One engine program. Along with the influx of modified Procars, several privately created Group 5 versions also appeared, including a design by Peter Sauber's sportscar firm.

The Sauber C5 prominently displayed Sauber's link with BMW.

The Swiss company had come from humble origins, initially constructing prototypes for national hillclimb racing. In 1976 the company made its debut on the world stage, racing a 2.0L Group 6 sportscar at Le Mans.

This car, the C5, was powered by a BMW M12 four cylinder engine, and prominently displayed the roundel emblem on the nose and rear body panels. The prior association with BMW made designing the Group 5 car that much easier, as Sauber received full cooperation.


Given the freedom afforded by Group 5, Sauber was able to completely rebuild the M1 from the ground up. Helped by the fact the M1 was already a tube frame car, Peter Sauber reconstructed it using lighter materials, extending and strengthening the frame where necessary.

The custom chassis was complemented by an exotic carbon fiber body, making the Sauber design the lightest Group 5 adaptation around. Since the car had been specially designed for Group 5 competition it was far lighter than its direct competitor from EMKA, which was nothing more than a regular Procar chassis augmented with Group 5-style body parts.


At just 970 kilograms (2138 lbs), the Sauber was some 150 kg (330 lbs) lighter than its lesser siblings. This gave it the opportunity to better utilize the M88/1 engine's limited power. The straight six was identical to the one used in Procar competition, producing some 470 horsepower at 9000 rpm and 390 Nm (299 ft lbs) of torque at 7000 rpm.

Although this was nothing to laugh at for a 3.5L naturally aspirated engine, it really wasn't enough to combat the dominant turbocharged Porsches. In fact, even 1.4L turbo cars like the Lancia Beta Montecarlo Turbo and the Zakspeed Ford Capri Turbo were able to push out up to 100 horsepower more. However, the M88/1 was really at the end of its development, making it impossible to safely extract more power from it.


Though BMW had been working on a turbo version with up to 1000 horsepower, development proved to be difficult and costly, as it kept breaking down. In the end, BMW abandoned the idea of the M88 turbo in favor of concentrating on its F1 program shortly before the M1 reached homologation. As a result, only close affiliate Team Schnitzer ever took delivery of the M88 turbo.


The lack of pure straight line grunt was somewhat compensated by having a reliable, proven engine concept, and superior fuel consumption to the thirsty turbo engines. Additionally, it permitted Sauber to keep using the same Hewland five-speed manual transmission, ensuring parts commonality and relatively easy servicing.

Though outwardly similar to its lesser brethren, the Sauber sported much wider bodywork extended by fitting large carbon fiber box sections, a bigger, deeper front airdam, extra vents over the front wheels, and a large, very distinctive NACA-duct in front of the rear wheel arches. However, compared to the EMKA and Schnitzer designs, the Sauber bodyshell was quite conservative.

GS-Sport M1R.

Two chassis were manufactured, and imaginatively dubbed M1R. Chassis M1R.01 was retained by Sauber dressed in colors emulating the French and Italian flags and sponsored by German hardware company Wurth, while the second car was sold to German team GS-Sport and adorned in the striking red and white color scheme of BASF Cassettes.

Both teams drew from a pool of established M1 Procar racers, as GS-Sport managed to attract former F1-driver Hans Joachim Stuck (GER), and Brabham F1-racer Nelson Piquet (BRA). Meanwhile, Sauber Racing Switzerland secured the services of BMW ace Dieter Quester (AUT) and F1-regular Marc Surer (CH).

Sauber Racing Switzerland M1R.

After a botched entry to the Silverstone 6 Hours, where GS-Sport was forced to turn to their Group 4 car, both M1R chassis finally made their debut at the 1981 Nurburgring 1000 Kilometers held on the legendary Nordschleife.

There the cars would have to face off against the turbocharged fury of the Zakspeed Ford Capri Turbo, the Lancia Beta Montecarlo Turbo and numerous different versions of the Porsche 935.

SRS BMW M1R negotiating the Hatzenbach, Nurburgring 1981.

Aided by HJ Stuck's Nurburgring expertise, the GS-Sport car qualified 5th overall, even beating out several Porsche 908/3 Turbo Group 6 prototypes. The Sauber Racing Switzerland car was decidedly slower, placing 10th.

The order didn't change on race day, as the SRS car retired with a broken exhaust, though it was still classified as 13th. The bright red BASF Cassettes machine was a lot more successful however, as Piquet and Stuck pulled off an overall win on the car's debut. In the process, they had beaten the Joest Racing Porsche 908/3 Turbo of former F1-driver Jochen Mass (GER) and Reinhold Joest (GER) by a full 20 seconds.

Nelson Piquet on his way to a surprise victory, Nurburgring 1981.

After a dream debut on the famous Eifel mountain course, the cars were brought to the main stage: the 24 Hours of Le Mans. For unknown reasons, GS-Sport chose to enter their car as an IMSA GTX entry, while SRS kept their M1R in Group 5.

GS-Sport had added F1-driver Jean-Pierre Jarier (FRA) and touring car driver Helmut Henzler (GER) to the roster for the grueling day-long event., while SRS hired sportscar specialist David Deacon (CAN).

Again both cars performed admirably in qualifying, punching far above their weight by placing 5th (GS-Sport) and 6th (SRS) in class. However, the fastest Sauber was some eleven seconds down on the class-leading 935, the Kremer K3/81 of Ted Field (USA), Bill Whittington (USA) and Don Whittington (USA).

Surprisingly, the lack of outright pace wasn't offset by the consistency, efficiency and reliability expected from the BMWs. Just 57 laps into the race, the GS-Sport car crashed out of the race, putting a major dent in its carbon fiber bodywork, as well as Sauber's hopes for a good finish. Exactly 150 laps down the line, the second M1R suffered an engine failure, making the event a complete disaster.

With their international debut ending in tears, Sauber refocused their attention to the Deutsche Rennsport Meisterschaft (German Racing Championship) a popular national series for Group 5 machinery. First up on the agenda was the Norisring Trophae, held on a claustrophobic street circuit.

Start of the race, Norisring 1981.

Being a sprint event, both teams reverted to using only a single driver in their cars. GS-Sport elected to drop Nelson Piquet in their car, while Dieter Quester assumed driving duties for SRS. Piquet qualified a fine 3rd, while Quester was further down in 7th.

Dieter Quester, Norisring 1981.

Neither car was able to impress on the tight and bumpy track, as Nelson Piquet finished a distant 7th, one lap down on the winning Kremer Porsche 935 K4 driven by Bob Wollek (FRA). Dieter Quester was even further behind, finishing 8th, two laps down.

Nelson Piquet, Norisring 1981.

Next up on the DRM calendar was Salzburgring event, held at a small, simple valley circuit. Only the SRS car attended the race, in the hands of Dieter Quester. The Austrian qualified a decent 6th, but was forced to abandon the race after being faced with electrical issues,

The cars reunited at the Hockenheim Grand Prix, a venue famous for its long straights cutting through a dense forest. Naturally, the underpowered M1R's weren't exactly at home at the high speed track, especially with the tremendously powerful Schnitzer M1 Turbo present.

The M1Rs chasing the various Porsches 935, DRM Hockenheim 1981.

Unsurprisingly, the GS Sport car driven by experienced European Formula Two driver Christian Danner (GER) placed a mere 9th on the grid, closely followed by experienced M1 racer Walter Nussbaumer (CH) in the sister car.

Though Danner was able to improve quite a bit to recover a 6th place on race day, Nussbaumer was not so lucky. A failing water pump put paid to his chances, taking him out of the running prematurely.

After the disappointing showing at Hockenheim, the teams prepared for a decidedly more suitable venue: the compact Zolder circuit in Belgium for the Westfalen-Pokal. As the track put a lot less of an emphasis on outright power, the Saubers were finally able to set competitive times again.

Christian Danner lined up in a fine 3rd place on the grid, with Walter Nussbaumer in 5th. Daner was able to retain the position in the race, but had to concede a lap to the winning Zakspeed Ford Capri Turbo driven by Klaus Ludwig (GER).

Meanwhile Nussbaumer was struck by bad luck again, failing to finish the race. Nussbaumer put a bow on his season back at Hockenheim however, as he finished third in the ADAC Hessen Cup.

The unusual Start und Zielschleife.

The cars parted ways after Zolder, with Sauber Racing Switzerland entering their car for the DRM Supersprint at the short 2.2 kilometer"Start und Zielschleife" (Start and Finish track) of the Nurburgring, a simple circuit much like Berlin's AVUS-Ring.

Again hampered by a lack of top end power, Walter Nussbaumer set a time good enough for 7th on the grid, 4.090 seconds behind the pole-sitting Porsche 935 K4 of Bob Wollek. Sadly, the M1R failed to reach the finish, as it succumbed to a torn suspension mounting cause by the crankshaft violently freeing itself from the engine.

Hans Joachim Stuck and Hans Heyer at Brands Hatch, 1981.

With the Sauber factory car being laid to rest, GS-Sport remained to take on a new challenge. Graced with a returning Hans Joachim Stuck and sportscar guru Hans Heyer (GER), the red M1R set out to tackle the riveting Brands Hatch circuit for a 1000 Kilometer event.

The mid-speed, twisty, high-downforce layout of the track suited the light and nimble M1R perfectly, helping it climb to 5th on the grid. Unfortunately though, Hans Joachim Stuck was caught in a terrifying accident which utterly destroyed the car. Already damaged heavily from the impact, the car ignited and burned to a crisp, being completely destroyed in the process.

The red M1R was lost at Brands Hatch.

With the FIA's roll out of an entirely new class structure across the board, the Sauber M1R effectively became obsolete on the international scale. As Group 5 was replaced by the heavily manufacturer-dependent Group B GT racing, and the lucrative Group C prototype class presented itself, Sauber wisely decided to bet on the best horse.

The surviving Sauber BMW M1R running with BMW Italia.

In order to fund the construction of their new C6 Group C racer, the remaining M1R was sold off to Eggenberger Motorsport, which operated under the BMW Italia banner. Driven by touring car veteran Umberto Grano (ITA), GT racer Enzo Calderari (ITA) and the immensely experienced Helmut Kelleners (GER), the car made its second appearance at the Nurburgring 1000 Kilometers.

Once again the car was successful at the tough endurance race in the Green Hell, scoring another podium with a fine 3rd place overall and 1st in class. A one-off appearance in DRM saw the car finish 10th in the hands of Enzo Calderari, climbing from an 18th grid position. At the Spa 1000 Kilometers, the car qualified 26th, but was forced to retire with engine failure.

The M1R in Kreepy Krauly livery.

The M1R was then repainted in the colors of Kreepy Krauly, a manufacturer of outdoor pool cleaning machines, and sent off to South Africa to race in the Kyalami 9 Hours. In the hands of Calderari, Grano and touring car racer Eddy Joosen (BEL), the car qualified 11th and finished a strong 7th.

The car made one final appearance under the BMW Italia flag long after Group 5 had died to contest the non-championship 3 Hours of Switzerland. Naturally, since motorsport had been banned in the country since 1955's Le Mans disaster, the race was actually held at Hockenheim.

At the very end of its career, the M1R scored its final major victory by beating a motley crew of 2L prototypes and ageing Porsches 935. Following the FRC 3 Hours of Switzerland, the car was sold off again to an unnamed Danish driver, who ran the car in local competition for a few years until Peter Sauber decided to track his creation down.


Sauber bought the car back in the late 1980s as one of the first items to grace his private collection, and restored it to its original glory. However, the car laid dormant from 1987 to 2013, and was rarely seen outside of Sauber's collection hall.

After keeping the car under wraps for 26 years, Peter Sauber decided he needed to pass the M1R on to an owner with the time to properly enjoy it. Through a mutual friend, he learned of Porsche hobby racer Adrian Gattiker. Sauber and Gattiker got better acquainted, and a sizable money transfer later, Gattiker was the happy owner of the unique Group 5 monster.


Following the purchase, Adrian Gattiker organized a full overhaul of the stagnant car, something Peter Sauber happily obliged to by tracking down the mechanic who had done the original wiring loom.

Now fully refurbished in every detail, and perhaps in better shape than ever, the car and Gatticker enjoy quiet track days together, as the prospect of a crowded historic racing event raises concerns over damaging the priceless car.