When was the last time you saw a C1-series Audi 100 Coupé S? Not recently, we’d bet. Less than 3200 made it onto the UK market and, of those, fewer than 50 are thought to have survived. In terms of rarity, this is up there with the Iso Grifo and Aston Martin DBS it so closely resembles.
It matches the Grifo and DBS in terms of lounge-lizard looks, too. Back in 1973, when the car in our photos was first registered, it was considered to be little more than an overpriced Volkswagen lookalike, but today the car has matured into a svelte, hunkered-down GT that carries with it more than a whiff of 1960s Mustang. Simply put, it’s absolutely stunning, especially with our test example’s vivid metallic blue paint and delicate chrome. 
Enough gawping. We need to go for a drive. Grasp the substantial chrome door handle, thumb the equally jumbo-sized push-button beneath and haul open the large, heavy door before stepping down into a world of 1970s Teutonic splendour.
Sink into the vast blue driver’s seat and pause awhile to drink in the details the almost comically huge steering wheel, the wood trim that calls to mind the teak you used to get on ’70s music centres, the Size 10 organ pedal throttle, and the quartet of green-on-black dials garnished with bright orange needles. Push the ignition key into the slot to the left of the steering column and the 1.9-litre fourcylinder engine coughs into life before settling into a slightly offbeat thrum that carries a vague timbre of the quattro’s trademark fivecylinder burble that would follow years later.
Then you go to snap your seatbelt into place, and puzzle over the apparently broken set-up missing its metal buckle. The penny drops…the Germans did things differently back then. Instead of a buckle, you loop the belt into a snap-jaw mechanism bolted to the floor. Well, it’s better than nothing…
The gearshift is one of few chinks in the 100’s armour – the throw is very long and rather vague, and each gear hits home with an indistinct slush rather than a rifle-bolt click – but the 1.9-litre ‘four’ is a little honey that punches well above its weight.
The long-winded gearbox takes the sporting edge off the car, but the engine delivers a hardedged engine note as the revs rise, and there’s an impressive amount of feedback through that Ark Royal tiller of a steering wheel.
Handling is on the soft side, but there is an almost boundless supply of grip. The rearwheel drive chassis feels surprisingly lively, given that it’s a simple live axle; no doubt the rear end becomes quite entertaining in the wet.
As a consummate cruiser, however, the Audi impresses, despite its lack of a fifth gear. While 118lb ft of torque doesn’t sound like much, it comes on song at a relatively lowly 3500rpm, meaning motorway overtakes rarely require a drop down into a lower gear. 

Audi 100 Trivia

• Just over 30,600 100 Coupés were sold during the C1’s production cycle. Its UK price at launch was a whopping £2418.
• All 100 Coupés were fitted with an advanced (for the time) brake stabilisation system that claimed to eliminate skids and unruly pulling to one side.
• There is a UK club dedicated specifically to the Audi 100 Coupé S.
• It is generally agreed that cars built up to 1973 used a higher grade of steel than those built from 1974 onwards.
• The 1.9-litre engine in well-maintained cars routinely covers more than 100,000 miles without a rebuild, with 150,000-milers by no means unheard of.