Volume production of the 1004 coupé started in May 1962, and in January 1963 saloon/sedan and cabriolet versions joined the range along with the more powerful Glas 1204.

Product developer Leonhard Ischinger, who had joined Glas from BMW, had produced a four-cylinder OHC engine with valve gear driven using a toothed rubber cam-belt, which at that time was a novel idea.

In 1961, the company added a modern coupé body using the chassis of the Glas Isar which for this application had been lengthened by 10 cm.

The car retained the water cooled 992 cc engine of the prototype which at this stage still delivered a claimed 42 PS (31 kW) of maximum power at 5,000 rpm.

Drive was to the rear wheels via a four-speed manual transmission incorporating – still slightly unusually for this size of car – synchromesh on all four forward speeds.

Press comment in a country where technical innovation generates enthusiasm was very positive in respect of the car's status as the world's first production car to be fitted with a belt driven camshaft, but criticised the unresponsiveness of the standard drum brakes and the heavy clutch.

A 1204 TS driven by Gerhard Bodmer finished in eighth position of the 86 cars that started in the 500 km Nürburgring race, achieving a class win in the process.

The Bodmer/Schmidt partnership were equally successful in the Spa-Francorchamps 24 hour race, finishing eighth overall and achieving a class win ahead of their team-mates Lambrechts and Mombaerts in another 1204 TS.

[4] A single carburetter version of the 1304 engine also became available in 1965, which still offered 44 kW (60 PS) of power and commensurate performance.

Also in September, an updated entry level 1004 was introduced, horsepower on the 992 cc engine now reduced to 40 PS (29 kW).