25 Years Ago: Opel Wins World Touring Car Championship with Calibra
Rüsselsheim. The 1996 season offered touring car racing at its finest. The Class 1 machines featured technology that was on a par with that in Formula 1. With the blessing of the FIA, the German DTM had become the International Touring Car Championship (ITC). The races took place around the world, from Hockenheim in Germany to Sao Paulo in Brazil. They were broadcast live on television and every race had fans glued to their TV sets – with famous drivers and thrilling overtaking manoeuvres. At the end of the season, Opel celebrated the biggest success in its racing history by winning the championships for both drivers and makes – against fierce competition from Alfa Romeo and Mercedes. The 1996 touring car champions were the Opel Calibra V6 4x4 and Manuel Reuter.
The driver line-up was peppered with stars. Former Formula 1 drivers like Alessandro Nannini, JJ Lehto and Hans-Joachim Stuck competed against young stars like Giancarlo Fisichella and the DTM winners Nicola Larini (1993), Klaus Ludwig (1994) and Bernd Schneider (1995). In the international series, the works teams Joest, Rosberg and Zakspeed were on the grid for Opel. The Class 1 touring cars were bursting with high-tech: V6 engines with 2.5 litre displacement and 500 hp, thoroughbred chassis; and in the case of the Opel Calibra, with all-wheel drive including ABS and a semi-automatic transmission with which the gears were changed in fractions of a second via paddles on the steering wheel. The lap times of the ITC touring cars reached those of the Formula 3000 – the final preparatory series for aspiring Formula 1 drivers at the time.
The 1996 ITC season
For Opel, the season began with a dream start at home in Hockenheim. On April 14, 1996 – 25 years ago today – Manuel Reuter took victory in his “Cliff” Calibra in the first of the two rounds. The driver from Mainz, Germany finally secured the championship in a turbulent rain race in Sao Paulo, in which he was able to leave his biggest rival for the title, Mercedes driver Bernd Schneider, behind. In addition to the driver’s title, Opel also took first place in the manufacturer’s championship at the season finale in Suzuka, Japan with 349 points, ahead of Alfa Romeo (340 points) and Mercedes (305). Nine victories – four by Klaus Ludwig (Opel Team Zakspeed), three by Manuel Reuter (Joest), two by "Strietzel" Stuck (Rosberg) – as well as 19 further podium places in 26 races were claimed by the Calibra drivers.
Technology of the Opel Calibra V6
With a V6 engine based on that of the Opel Monterey, the Calibra had around 500 hp at its disposal for the 1996 season. Further development was carried out by Cosworth Engineering during the season. The aluminium block saved weight compared to its predecessor. The wider bank angle (75, previously 54 degrees) led to a lower overall height and thus a more favourable centre of gravity; it also allowed for flatter air intakes.
In addition, there was a hydraulically operated, six-speed, semi-automatic transmission. The technology, developed together with Opel's partner Williams GP Engineering, relieved the driver's workload, especially in tricky racing situations, and prevented over-revving of the power units. A high-pressure hydraulic system operated the sequential gearbox. The driver shifted gears either via paddles behind the steering wheel or by pressing a button. The Calibra needed just 0.004 second to change gears, including engaging the clutch.
Another hydraulic system varied the pressures in the differential locks. Sensors measured wheel slip and the electronic control unit converted the information into the optimal hydraulic pressure – increasing it under acceleration, for example, and thus closing the differential lock. Once the track and thus the traction behaviour at every point had been recorded in the computer, the locking of the differentials – as well as the automatic adjustment of the stabilisers (aka anti-roll bars) – could be programmed. The road-holding of the ITC Calibra was also significantly improved by the work of the aerodynamics specialists: in 200 wind tunnel hours, they increased downforce by an astonishing 28 per cent.
With the Opel triumph at the end of the 1996 season, the era of Class 1 touring cars had reached its peak. The highly bred "Formula 1 with a roof" had become too expensive in terms of development and running costs. The ITC became history after only two years. In 2000, the DTM – now called the German Touring Car Masters – celebrated its comeback with new, technologically simplified regulations and again with works teams from Rüsselsheim. Manuel Reuter captured two victories with the Opel Astra V8 Coupé. Joachim Winkelhock and Uwe Alzen also celebrated first-place finishes.
Today, most of the touring cars from the ITC and DTM eras stand side by side in the Opel Classic collection. The black and white “Cliff” Calibra from 1996 is parked right at the front. The world champion has stood here in pole position unchallenged for 25 years.
Opel Teams in the 1996 ITC Season
Driver number 7 Manuel Reuter (D, ITC Champion)
Driver number 8 Oliver Gavin (GB)
Driver number 24 Yannick Dalmas (F)
Driver number 25 Alexander Wurz (A), Tony Kanaan1 (BR)
Driver number 27 Masanori Sekiya1 (J)
Driver number 43 JJ Lehto (FIN)
Driver number 44 Hans-Joachim Stuck (D)
Driver number 16 Uwe Alzen (D)
Driver number 17 Klaus Ludwig (D)
Driver number 23 Volker Strycek1 (D)
Giudici (Private team)
Driver number 13 Gianni Giudici (I)
 These drivers were guest participants in selected races