Group B: The Rally Cars That Outran Their Own Rules

A homologation rule with a very low bar

In 1982, the FIA rewrote the rulebook for top-level rallying. The new class, Group B, replaced Group 4 and cut the homologation requirement drastically: a manufacturer now only had to build 200 road-going examples of a car to qualify it for competition, and as few as 20 additional units to homologate a mid-season "evolution" version. Group 4 had required 400. On paper it looked like a minor bureaucratic change. In practice, it removed almost every constraint that had kept rally cars close to anything a customer could actually buy, and manufacturers understood exactly what that meant within a season or two.

Four-wheel drive changes the argument

Audi had already shown what was coming. The Quattro, campaigned from 1981 under the outgoing Group 4 rules, used a permanent four-wheel-drive system in a class that had been dominated for years by lighter, rear-wheel-drive cars from Lancia, Fiat, and Ford. Traction, not outright horsepower, turned out to be the decisive advantage on loose surfaces, and rival manufacturers spent the early Group B years racing to catch up. Lancia held out the longest: its 037, a supercharged, rear-wheel-drive car, beat Audi to the 1983 manufacturers' title on chassis balance and driver skill alone. It remains the last rear-wheel-drive car to win a World Rally Championship title. Every major manufacturer that followed built around four-wheel drive.

The horsepower race outran the engineering

Once traction stopped being the limiting factor, power became the battleground, and Group B's minimal weight limits let manufacturers chase it aggressively. Lancia's Delta S4, introduced in 1985, ran a 1.8-litre engine with both a supercharger and a turbocharger, the supercharger covering low-end response while the turbo took over at higher revs, a setup built specifically to eliminate turbo lag on cars that needed to accelerate hard out of hairpins with no warning. Peugeot's mid-engined, all-wheel-drive 205 Turbo 16 took the title in 1985 and 1986, with its final Evolution 2 works cars reportedly producing in the region of 500 horsepower from roughly 1.8 litres, in cars that weighed under a tonne. Contemporary reports and period road tests put some Evolution-spec Group B cars at under three seconds to 100 km/h, quicker off the line than the Formula 1 cars of the same era.

Speeds no closed road was ever built for

That power arrived faster than the sport's safety infrastructure could keep up with it. Rallies were run on public and forest roads, closed for competition but lined with spectators standing feet from the racing line, often with no barriers at all. Cars capable of triple-digit speeds on loose gravel gave drivers almost no margin for a mechanical failure or a misjudged line, and by 1986 the risk caught up with the sport in quick succession. Early that year, a car left the road at the Rallye de Portugal and went into a crowd of spectators, killing several and injuring dozens more. In May, works driver Henri Toivonen and co-driver Sergio Cresto were killed when their Lancia Delta S4 left the road on the Tour de Corse and caught fire. Toivonen had been considered the fastest driver in the category.

The ban, and what replaced it

The FIA moved fast. Group B was withdrawn from international rallying at the end of the 1986 season, with a planned 1987 evolution of even more powerful "Group S" cars scrapped entirely before it ever competed. The championship moved to Group A regulations, built around genuine production cars with far higher homologation volumes and tighter power limits. Rallying became slower, and safer, almost overnight.

Why the era still gets talked about

Group B lasted barely four seasons, but it is still the reference point every rallying conversation about outright speed gets measured against. It answered, briefly and conclusively, what happens when a regulator removes almost every constraint on a race car at once: manufacturers will find the limit, and it will be well past what the surrounding environment can safely absorb. That's a rare thing in motorsport, a set of rules that worked exactly as written and had to be undone specifically because of it.

If that kind of no-compromise engineering is what draws you to a build in the first place, our Cars collection is built around the same instinct: models that exist because the real car pushed a limit somewhere, not because it looked good from across a room.