Porsche has just completed restoration of a 924 Carrera GTS rally car. The project was a surprise for the 74th birthday of rally driver Walter Röhrl.
Röhrl is a racing legend, but the German native has officially raced for Porsche for only one rally season. That was 40 years ago, behind the wheel of this gold-and-black 924 for the 1981 season of the German Rally Championship. Röhrl and co-driver Christian Geistdörfer won four races and came in second overall in the championship points standings. After that, the duo signed on to the Opel team and Röhrl went on to drive other legendary cars.
Back in 1981, the 924 Carerra GTS was the most expensive car Porsche had ever produced up until that time. Only 50 of the Group 4 (predecessor to Group B) homologation specials were made, all painted in Guards Red. The GTS made 237 horsepower while a more powerful (and rarer) Clubsport variant made 271 hp.
An additional nine prototypes were built, of which Röhrl's rally car was the fifth. The race car started out with 247 hp but power was added as the season went on. It has had a number of special features as well, including a fiberglass coating for the axle links from the innovative rear transaxle to protect against rocks, skid plates beneath the oil pan and gearbox, and a fuel distributor from the V8-powered 928.
The painstaking restoration was conducted at Porsche's historic motor racing department in Weissach, the same garage where the car was born on December 12, 1980. The restoration team strove to preserve as much of the original car as possible.
Its 2.0-liter turbo four, a heavily re-worked Volkswagen EA831 unit, has no serial number. It was meant as a test car, but ran the entire season on the original motor. The odometer reads just 10,371 km (6,444 miles), but those were hard-driven. Traces of the car's time spent on gravel-laden special stages were preserved, as were the original racing harness belts (sun-worn, but embroidered with the initials "R" and "CG").
The paint, however, is new. After Röhrl and Geistdörfer's stint, the 924 was repainted in blue to welcome the sponsorship of Gitanes cigarettes. The resto team decided to bring it back to its original livery, the gold and black of Monnet cognac.
Porsche says that consumables, a few chassis components, and the fuel supply system were replaced. They rebuilt and kept components like the original brake calipers, borrowed from a 911 Turbo, custom intercooler housing, and KKK 26 turbos. The Porsche Museum workshop even donated an original race clutch for the car, and Pirelli was able to scare up a set of 255/55-R15 tires with the original tread pattern.
Turbocharging was still a new technology at the time, and Röhrl recalled that it presented a steep learning curve. "The turbo lag was enormous! In order to drive out of bends quickly, you had to accelerate again shortly before the bend and keep the engine speed high."
Kuno Werner, head of the museum workshop, said that the toughest part of the restoration was keeping it a secret from Röhrl, who has many friends at the company. However, the managed to keep the surprise under wraps until the legend's 74th birthday.
"It was a huge surprise for me, said Röhrl upon seeing the 924. "I stepped out of the car 40 years ago and haven’t sat in it again since." He continued, "For me, it’s a journey back in time. I immediately feel 40 years younger."