Porsche
911 Turbo (930) “Flachbau” flat-nose (factory special programme)

Why it matters

The 930 Flachbau was the first limited series of Porsche's Exclusive (Sonderwunsch) department and brought the look of the 935 racing car to the road-going 911 Turbo. With 984 sold between 1982 and 1989 it is a rare factory specification of the otherwise common 930.

How rare is it?

Six separate kinds of rarity – never combined into one number.

Each kind of rarity is rated separately and never combined.

Production

Every figure says what it counts.

Independent counts (e.g. engine and colour) are never combined into a calculated figure. Surviving examples are never presented as original production.

History

In 1982 Porsche racing sponsors asked for a road car resembling the 935, and the Sonderwunsch programme answered with a lowered flat front on the 911 Turbo, with folding headlights and modified front wings. The conversion was initially built to individual order; in 1987 it entered the North American catalogue as option M505, with M506 used for other markets. For the 1988 model year 148 North American Turbo coupés received the M505 package, which cost close to $30,000 extra. Porsche quotes 984 cars sold from 1982 to 1989.

Technical specifications

Engine

Transmission & drivetrain

Chassis, body & dimensions

Performance

“Not yet verified” means no source has been checked for that value yet. Nothing is estimated to fill a gap.

Identification guide

How to tell an original from a replica or later conversion.

Factory cars have louvred steel front wings flush with the bonnet, retractable headlamps, boxed sills extended to the widened rear quarters, brake-cooling vents with strakes in the rear quarter panels and an electric fan for extra oil cooling. Option code M505 (North America) or M506 (rest of world) should appear on the car's documentation, ideally confirmed by a Porsche Certificate of Authenticity.

Sources

Each number links to the exact facts it supports.

1. 1
   Porsche Newsroom: Porsche Exclusive makes nearly all dreams come true Level A

   • 984 units sold 1982–1989

   Accessed 2026-11-12
2. 2
   1988 Porsche 911 Turbo 'Flat-Nose' Coupe (Porsche 70th Anniversary Auction, lot 172) Level C RM Sotheby's

   • 3.3-liter Turbo coupe was built with the desirable '930S' flat-nose option
   • all-steel M505 930S 'Flachbau' package with its vented front fenders

   Accessed 2026-11-12
3. 3
   1983 Porsche 930 Turbo Series 1 Flachbau Conversion (Greenwich 2022) Level C Bonhams

   • 3,299cc SOHC Turbocharged Flat Six Engine
   • Bosch K-Jetronic Fuel Injection

   Accessed 2026-11-12