Peugeot 405 Turbo 16 – Group S Prototype

peugeot-405-t16-groupe-s-3
Peugeot 405 Turbo 16 – Presentation Version

In 1985, the FISA (former ruling committee of the FIA) announced a possible replacement class to Group B that was referred to as “Group S”. The new regulations would require only 10 cars for homologation and was essentially a “prototype” class for rallying. The class was originally scheduled to make its debut on January 1st 1988, then as a heavily revised replacement to Group B for 1987, but both were ultimately cancelled. To learn much more about the history of Group S, please CLICK HERE!

For the 1987 Group S replacement formula, Peugeot Talbot Sport (PTS) actually wanted to perform what a third evolution (E3) of the 205 T16. The main improvement planned for the car was in the drivetrain system. A new transmission was in development which would be equipped with a driver adjustable center differential to be able to balance front to rear torque distribution on the fly. This feature was also seen as a safety measure to help properly set the balance of the car. It is sometimes referred to as Peugeot’s “Group S transmission”. The car would also have received new aerodynamic enhancements. For the rest, the rally car would have simply been adapted to the new regulations; i.e. use of ballasts to reach the new higher minimum race weight.

By then, even though the 205 T16 had been very successful, the engineers had always seen an inherent flaw with the car: the wheelbase. At 100 inches, it already was one of the longest among Group B cars, but the engineers wanted to stretch it even further to gain more stability. However, this proved to be almost impossible since it was ultimately limited by the 205 model’s design. Peugeot Talbot Sport team boss Jean Todt specified that this was a factor in the team’s loss to Audi at Pikes Peak even if they fielded a fleet of three specially prepared 205 T16 E2 PPs for the event.

The adventure to fix this issue first started in late 1986 with a special version of the 205 T16 made specifically for the Paris-Dakar endurance race. The chassis was reinforced substantially and elongated by 12 inches (30 cms) between the engine and the passenger compartment to accommodate a 350 liter fuel tank. The much longer wheelbase would help give the car the more stable footprint the engineers so desired. However, this modification no longer made the 205 T16 look appropriate in its exterior appearance, to which Peugeot took much disdain.

For 1987, Peugeot was about to release a new model, the 405, which was much longer than the 205. The company could help market the new car with a special competition version exactly like the 205 Turbo 16 did with the normal 205 back in 1984.

The 405 T16 and its XU9T engine on display.
The 405 T16 and its XU9T engine on display.

It was a no-brainer for Peugeot Talbot Sport to simply adapt the very proficient 205 T16 chassis and drivetrain for the new 405 model. The revised chassis, albeit very similar, was now fully tubular and stretched to fit the required dimensions. This new longer chassis naturally made the wheelbase increase from the 205 T16’s original 100 inches to match the 405’s 113.7 inches. Besides this, the basic 405 T16 was reported to weigh only 880 kg (1940 lbs). The lengthened section of the chassis would also allow to fit larger fuel tanks aimed specifically for the rally raid version. In all, the increased length simply made the car more versatile.

peugeot-405-t16-groupe-s-4

It is worth to mention that the normal 405 model was a 4-door sedan which was gracefully adapted to a 2 door coupé in T16 form, resulting in a much better aerodynamically flowing car than the 205 T16. It sported very advanced ground effects blended in a seamless, very mature design. By looking at the overall quality of the 405 Turbo 16 Presentation Version, one could argue that it could have easily been the company’s new “Serie-200” homologation road car if Group B was never cancelled.

Further improvements were made to the T16 engine package as Peugeot was no longer restricted by the Group B displacement class rules. The XU8T’s engine displacement was increased to 1905 cc and fitted with new technologies such as dual variable valve timing and a variable geometry turbocharger. The drivetrain improvements that were planned for the Group S 205 T16 “E3” were implemented in the 405 T16 instead. After toying with an experimental automated clutch (sequential) transmission, it was ultimately left out for a simpler “TJ” type unit but which sported the new driver adjustable center differential system.

In 1984, Peugeot also produced a concept car, the Quasar, that utilized the 205 T16 chassis and drivetrain. It featured 600 HP and a lot of advanced cool bits!
1984 Peugeot Quasar – Concept Car

In 1984, Peugeot also produced a concept car called the Quasar that utilized the 205 T16 chassis and drivetrain. It featured 600 HP and a lot of advanced cool bits. It is often mistaken to be Peugeot’s Group S car.

As events would unfold, the FISA ultimately cancelled Group S but that would not stop the 405 Turbo 16’s development as Peugeot’s flagship rally model in other related venues.

PIKES PEAK

405 Turbo 16
405 Turbo 16 “Pikes Peak”

The car would undergo a special modification to participate in the 1988 Pikes Peak hill climb race. The 405 T16 Pikes Peak gives a glimpse of what the Group S car would have looked like in full rally competition trim. The car would give Peugeot victory at the event in the capable hands of Ari Vatanen. He bettered Walter Röhrl‘s previous year record of 10:47.850 by a few tenths of a second (10:47.220): a record that stood until 1994. The feat was also immortalized in the award wining short movie “Climb Dance”. It is worth mentioning that Robby Unser competed in the 1989 running of the race with an identical 405 T16 and gave the car a second straight victory.

GRAND RAID

Peugeot 405 T16 GR PD
405 Turbo 16 “Grand Raid”

The car was also modified to participate in “Rally Raid” events. The 405 T16 GR sported a longer stroke reinforced suspension and a much larger fuel tank that sat in between the cabin bulkhead and the engine. Besides a cursed debut in 1988, Ari Vatanen and the 405 would again pair up and deliver to Peugeot wins at the 1989 and 1990 editions of the famous Paris-Dakar race. Immediately afterwards, Peugeot Talbot Sport decided to officially retire the 205/405 T16s from competition to concentrate on the development of the 905 prototype racer in the World Sportscar Championship. However, this would not be the last victory for the proven Peugeot T16’s engineering: sister PSA company Citroën would use it as the base for its ZX Grand Raid vehicle which would subsequently win the Paris-Dakar event 4 times from 1991 through 1996, officially retiring in 1997.

1991-citroen-zx-gr
Citroën ZX

This means that the 205 Turbo 16 was a design that came to be competitive for over a decade: an achievement that is seldom seen in motorsport and a testament to Group B’s influence.


(C) Article by Jay Auger – website owner & author

  • Images & videos are the property of their original owners

Do you want to contribute information or pictures to this page? Please feel free to do so by using this CONTACT form!

(C) WELCOME TO THE ENCYCLOPEDIA OF THE GOLDEN ERA OF RALLYING