A road car wearing the face of a race car, built to special order.
Where the face came from
The slantnose started on the track. The 935, Porsche's dominant Group 5 race car of the late 1970s, used a flattened front end with pop-up headlights in place of the production 911's upright round lamps. The change was aerodynamic, a lower, smoother nose that cut drag and added front downforce, and it became the 935's signature look as the car won race after race through that era.
Customers saw the race cars and wanted the look on the road. Porsche responded by offering the slantnose front end as a factory option on the 930 Turbo, known by the German name Flachbau, meaning flat-build. Where the standard 911 had its round headlights sitting upright at the front of the fenders, the Flachbau had a flat, sloping nose with the headlights hidden in pop-up units, lifting the racing face directly onto the road car.
How it was built
The factory Flachbau was a genuine special-order item, expensive and produced in small numbers. The conversion was substantial. Reworking the front of a 911 to the slantnose shape was hand work, and the cost reflected it. In the United States the option carried its own order codes, and a factory slantnose commanded a significant premium over the standard Turbo when new.
That rarity and that cost matter, because the slantnose look was widely and badly copied. Through the 1980s the aftermarket produced countless slantnose conversion kits, bolting a crude version of the look onto ordinary 911s. The result is that most slantnose 911s on the road are not factory cars at all. They are aftermarket conversions, and they are worth a fraction of the genuine article. Telling the two apart is a real skill, and it is central to buying one.
Why it divides collectors
The Flachbau has always split opinion. To some it is the ultimate expression of the Turbo, the road car that most directly channels the racing cars that made the 911 a legend on track. To others it is a period excess, a styling fashion of the 1980s that obscures the classic 911 face everyone loves. Both views are defensible, and the debate has never really settled.
What is not in question is the value gap between real and fake. A documented factory Flachbau is a rare and increasingly appreciated car, sought precisely because so few were built and so many imitations exist. An aftermarket slantnose, however well done, is a converted ordinary 911 and is valued as one. The whole story of the slantnose, on the road as on the track, comes down to whether the car is the real thing.