Alfa Romeo 155 V6 TI DTM

Revisiting a legendary touring car champion

D-T-M – these three letters can make the hearts of dyed-in-the-wool racing enthusiasts beat a little faster. Originally short for Deutsche Tourenwagen Meisterschaft, DTM refers to what has arguably been the premier touring car championship in the world for many years. The DTM has traditionally been the playing field of German manufacturers like Mercedes-Benz, Audi, and BMW, and also attracted hugely talented and/or successful racing drivers that included the likes of Michael Schumacher, Mika Hakkinen, and Dario Franchitti.

Sadly, the series has been forced to reinvent itself ahead of the 2021 season after Audi announced its withdrawal from DTM at the end of this year. That left BMW as the only manufacturer fielding cars, which was not a viable situation. While DTM vows to continue, the changes will be drastic. This has prompted us to take a closer look at one of the all time great cars to compete in the series, which was actually not built by any of the big German companies but by Alfa Romeo.

The Alfa's high-revving V6 engine was very loosely based on a production block.

Production-based touring cars burst onto the scene in the 1960s with cars like the Ford Lotus Cortina and Alfa Romeo Giulia GTA going head-to-head. Seeing machines similar to what fans drove to the track in has always made touring car racing very relatable to spectators. With the cars themselves usually not nearly as precious as purpose-built sports prototypes or single-seaters, there usually was – and still is – close door-handle-to-door-handle racing. DTM has always been a bit different from most other touring car series, as it traditionally aimed at a slightly higher-market segment. As a result, the cars used in the DTM usually were not eligible for any other series, which required a fair degree of factory involvement. The most recent generation cars, for example, were silhouette racers, built around a bespoke, carbon-fiber monocoque, powered by a hugely powerful, turbocharged, four-cylinder engine. While this allowed for some spectacular racing, it also made the series difficult to enter and quite vulnerable to the whims of manufacturers. Ultimately, this proved to be its downfall.

There were no such concerns in 1993, when a brand-new set of regulations was introduced for touring cars. It was a two-tier system, split in the relatively lenient Class 1 and Class 2. The latter allowed for fewer modifications and featured a two-liter displacement limit. There were fewer restrictions in Class 1. The engine regulations stipulated the use of a 2.5-liter engine with a maximum of six cylinders and four valves per cylinder. This engine should be based on a regular production unit built by the same manufacturer but not necessarily fitted to the car the Class 1 touring is based on. The rulebook had no restrictions on electronic adds like ABS and traction control. With the exception of the rear wing, all aerodynamic devices should be mounted below the wheel centerline. It should have come as no surprise that DTM adapted the Class 1 regulations, while all other championships opted to run Class 2 cars. The first manufacturer to build an all-new Class 1 car was Alfa Romeo, basing its new touring car on the 155 sedan.

As per the regulations, all aerodynamic devices were placed beneath the center wheel-line with the exception of the rear wing.

Dubbed the 155 TI V6 DTM, the new Alfa Romeo Class 1 racer looked very similar to the production car. Upon closer inspection, nothing was quite what it seemed. While the DTM racer featured a shell that followed the same lines of the road car, it was made from thinner gauge steel. In fact, the shell was so thin that the mechanics had to be careful not to lean on the roof. The rigidity lost by making the car’s body lighter was more than compensated by the elaborate roll-cage fitted throughout the cabin. This tubular steel structure was effectively a space-frame chassis mounted inside the shell. All of the removable panels like the engine cover and doors were made from lightweight carbon-fiber composites. As stipulated, only the body sections below the wheel centerline were carefully shaped for aerodynamic benefit. The nose featured a deep splitter, while at the rear a full-width diffusor was fitted. Further downforce was created by the twin-element rear wing.

Literally, the beating heart of the Alfa Romeo DTM racer was its 2.5-liter V6 engine. As per the regulations, it was based on a production block. That did not stop the Alfa Corse engineers from creating what was effectively a downsized Formula 1 engine. In order to keep the costs down, a limit had been set at 12,000 rpm but the 60-degree V6 would have happily revved well beyond that. At its 1993 debut, the engine produced around 420 hp, which steadily grew to 490 hp by 1996. In addition to being hugely powerful, it was also light, tipping the scales at just 106 kg. Whereas the engine in the production 155 was mounted transversely, the 2.5-liter V6 of the DTM car was placed longitudinally, ahead of the front axle. It was mated to a transverse six-speed, semi-automatic gearbox. Sourced from the Lancia Delta HF Integrale rally car, a four-wheel drive system was fitted. The drive was split between 35 percent to 40 percent to the front and 65 percent to 60 percent to the rear.

One of the privately-entered 155 V6 TI's; this example was raced by Kris Nissen during the 1994 season, winning one race.

Double wishbones with coil springs over dampers were fitted on all four corners. The relatively long suspension arms were more akin to those found on an F1 car than on a production road car. The suspension was fully adjustable while the driver could also adjust the stiffness of the anti-roll bars through levers mounted next to the seat. The car was also designed with easy access of the mechanics in mind. A good example is the rear axle, which can be removed by loosening just six bolts. Stopping power was provided by ventilated disc brakes, sourced from Brembo. These were coupled with a sophisticated anti-lock braking system that was supplied by Bosch. Traction control was also fitted. Courtesy of all the lightweight components fitted throughout, the 155 DTM racer easily managed to make the prescribed minimum weight of 1,060 kg. The car had performance figures to match with the sprint from 0-100 km/h being completed in just 2.5 seconds and a top speed of in excess of 300 km/h.

The 155 V6 TI DTM was ready in time for the opening round of the 1993 DTM at Zolder in Belgium. Five examples cars lined up; two entered by the works team and a further three by privateers, who received a healthy degree of support from Alfa Corse. The factory cars were driven by ex-F1 drivers Alessandro Nanini and Nicola Larini. A fourth privateer car was added to the Alfa Romeo roster for the final six rounds of the championship. The main opposition for the Alfa Romeos came from Mercedes-Benz. The German manufacturer used a modified version of the 190E used during the previous seasons. Their C-Class based Class 1 car would not be ready until the start of the 1994 season. The only other purpose-built Class 1 racer to line up during the 1993 season was the Opel Calibra V6 4×4, which debuted in the final round of the year.

The carbon-fiber composite dashboard features a prominent digital rev counter.

Without question, the hugely sophisticated Alfa Romeo 155 V6 TI DTM had taken the competition by surprise. During the season opening weekend at Zolder, Nicola Larini qualified his car on pole position and he would go on to take the win in both heats. Christian Danner was second in both with a privately entered example. The Italian would go on to win a further eight heats out of the next championship eighteen starts. His compatriot Nanini would also score two wins, while both Larini and Danner won the heats at the non-championship round organized at Donington. With ten wins in twenty starts, Larini was the well-deserved Deutsche Tourenwagen Meister of 1993. Alfa Romeo also won the constructors’ trophy but with a surprisingly small margin over the very consistent Mercedes-Benz team.

With the arrival of the Class 1 Mercedes-Benz C-Class in 1994, the playing field was leveled. The result was a very spectacular championship with Alfa Romeos winning eleven of the twenty rounds. This was not enough to beat Mercedes-Benz touring car ace Klaus Ludwig to the punch. Despite winning just three rounds, his string of podium finishes helped him secure the championship. Larini, despite scoring five wins, was just third and Nanini, with three wins, placed fourth. Now three years old, the 155 V6 TI DTM struggled in 1995 and just five wins were scored. There was further change in the DTM that year as the series popularity saw the addition of the International Touring Car Championship, or ITC. These were effectively DTM races at international tracks like Mugello, Estoril, and Magny Cours. Mercedes-Benz driver Bernd Schneider was both the 1995 DTM and ITC champion.

The car's engine sits lower in the chassis than the wheels are tall.

For the 1996 season, the DTM name was dropped altogether as all thirteen rounds now counted for the ITC. The added appeal of a truly international championship prompted Alfa Corse to tweak the 155 V6 TI even further. The engine was both more powerful and lighter than before, which helped improve the performance. As in 1995, the factory cars were finished in the striking Martini colors. With ten wins in twenty-six starts, the 155 once again proved the most successful car in the championship. However, it was the much-improved Opel Calibra and driver Manuel Reuter that ended the year as champions. This was despite the German driver taking just three wins, compared with third-place Nanini’s seven.

While Class 1 racing proved very exciting to watch, it was also hugely expensive. This prompted both Alfa Romeo and Opel to suspend their efforts at the end of the season. Now the vulnerability of the series became painfully obvious as Mercedes-Benz was left as the only manufacturer willing to compete in 1997. It spelled the end of the championship that would not return until the 2000 season with DTM now short for the Deutsche Tourenwagen Masters.

One of the 1993 championship-winning cars, which is now part of the Alfa Romeo museum collection.

What is happening to DTM now has all the hallmarks of 1996 but instead of suspending the series, a different solution has been found. For 2021, instead of fielding “production-based” touring cars, the DTM will switch to GT3-based machinery. These are readily available and will finally make the championship accessible again for non-manufacturer teams. Ideally, the more diverse field will make up for losing the allure of full works efforts.

The 1993-1996 era of DTM/ITC will forever be fondly remembered, as it featured incredibly sophisticated machinery piloted by hugely talented drivers. Setting the gold standard at the start of the 1993 season, the Alfa Romeo 155 TI V6 racked up an incredible thirty-eight victories of a total of eighty-nine starts. The V6-engined machine also qualified on pole nineteen times and set the fastest lap in forty-two races. Following the 155’s circuit-racing career, some examples reappeared in the Italian hill-climb championship. One of these was scoring class wins as late as 2015.

Today, few examples are in private hands, but Italian historic racer Franco Meiners has two. He explains: “First of all, I watched all these races, they were spectacular, Mercedes-Benz against Alfa Romeo. I also had lots of friends driving in them.” Meiners continues: “Second, I found the technology as well as the rules amazing. I think the car was more advanced than a Formula 1 car of the same period. Look at the engine. It is sitting lower than the height of the front wheels. Tell me another race car where mechanics were able to change the engine in fifteen minutes between one stint and the other? Incredible! I liked the ’93 version, and also the ’94-’95 version. I did not want the ’96 version with the pneumatic valve system and lots of electronics.” The 155 V6 TI DTM clearly did not disappoint; Meiners concludes: “Lastly, if you have the chance to drive one – the sound, the revs, the set up! You drive a 155 and you think you are a professional Formula 1 driver, they are so easy to drive!”