Citroen BX 4TC Evolution ~ Failing Spectacularly #blogpost

Prior to 1986, French automaker Citroën was racing in Group B with their front wheel drive Visa rally cars and later with the four wheel drive Mille Pistes variations. They were low-power B-9 (under 1300 cc) and B-10 (under 1600 cc) cars aimed at their respective classes’ honours. However, Citroën also wanted to compete for the overall win in the B-12 (2000 cc +) class and gain much publicities. For that purpose, Citroën Compétitions, with engineering firm Heuliez, started to devise a BX-model based rally car which was developed alongside the Visa RWD & 4×4 prototypes. In all, 5 prototypes were built, all sporting different specifications, but all used variations of Peugeot’s X5N2 engine.

The final prototypes were confirmed by team boss Guy Verrier to be Citroën Competitions’ top Group B contender. The former being the competition version and the latter being the client “serie-200” homologation road model. Verrier wanted to link the rally car to the road-going BX, and he wanted to incorporate as many in-house parts as possible. As before with the Visa, all were built by Heuliez. From this came the BX 4TC Evolution. Citroën’s competition department built the 20 Evolution models at its headquarters in Trappe, and homologation was granted on January 1, 1986.

Choosing to follow a less ‘bespoke’ route placed the BX 4TC Evolution at a huge disadvantage. It ended up being a veritable mess of PSA parts thrown together. With hugely greater budgets, most of Citroën’s rivals had used a series of special, one off components to produce raw, feral machines, built without compromise. Verrier, driven by an emotional attachment to Citroën and a modest budget, oversaw the creation of something more domesticated yet, ironically, more difficult to control.

Group B’s winning recipe was its technical freedom; it dispensed with the need for manufacturers to rely on existing production models. Verrier and his team failed to embrace the spirit and failed to use the loose regulations to their advantage, sanctioning an outmoded concept which almost mirrored the original Audi Quattro. The engine was positioned in the front of the car. Despite being dry-sumped, fuel-injected and turbocharged, it was based on a 1970 Simca design with an iron block, alloy head, a single overhead camshaft and just eight valves. That said, it was a strong engine which produced 380 HP with a healthy 252 lb-ft. of torque.

Although the 4TC Evolution looked every inch a Group B monster, those outrageously-styled panels hid a weight problem. Essentially a monocoque construction, albeit with special tubular subframes, the BX 4TC weighed in at a hefty 1150 kg, well above the 960kg class minimum and considerably more than its closest opposition.

Two cars raced the first event on the 1986 WRC calendar, the Monte Carlo Rally. One was driven by Jean-Claude Andruet, who had won the 1977 Sanremo, the 1974 Tour de Corse and, more importantly, the 1973 Monte Carlo. Philippe Wambergue, a Citroën test driver who would later excel at rally cross and in Rally Raids, drove the other. Andruet recorded seventh and eighth fastest times before crashing out on stage six. Wambergue didn’t do well either, retiring on Stage One due to suspension failure.

In the Swedish Rally, asphalt expert Andruet surprised onlookers with his snow and ice pace, finishing sixth. Wambergue, who wasn’t far behind Andruet, had to ‘let it go’ with a Frozen oil pipe (Ik I’m hilarious) on stage 25.

After the rally’s let downs, Citroën pulled the BX 4TC out of the WRC on the spot. A brave yet misguided attempt, the BX 4TC Evolution was hampered by a limited budget, by being umbilically tied to its road-going version, a lack of technical development, and its late arrival. Worse still, by persisting with what was so obviously an outmoded concept, 1985 proved to be a wasted year. The BX 4TC Evolution was immediately outclassed by a raft of space-framed and mid-engine supercars which proved to be as nimble as they were quick.
By this time, due to the safety concerns, Group B was to be banned at the end of the year which probably made Citroën’s decision easier. Yet, the abysmal results would always remain in the company’s history: the BX 4TC is often referred as the worst attempt at a making competitive Group B car. Citroën was reportedly so distraught about their humiliating wasted efforts that it is rumoured they had most of the evolution rally cars destroyed (only 6/20 are currently accounted for today). Citroën would find solace in the fact that the subsequent cancellation of the Group S replacement formula would soon relinquish the rally supercars to a hazy memory.

This article is from https://rallygroupbshrine.org a website I recently found which could really use this community’s help. Run by one guy with amazing info. Go check it out!

~Maxwell (and Jay Auger)