In 1961, Volkswagen introduced the Type 3 line with the Notchback (See VW Notchback), and the Type 34 Karmann Ghia. The cars were also known as the VW 1500 series. They were intended to help VW get into the growing middle class who were buying BMW 1500/1800s and Opel Kadetts, In 1962, they followed with the Variant (Squareback in the USA) which was essentially a station wagon version. The type 3 did well, but was nothing like the Beetle in sales numbers. Seeking to bolster sales, in 1965 Volkswagen introduced the Fastback. It coincided with the new 1600 engine, giving the Type 3 cars a needed boost.
The Fastback was, as the name implies, a two door type 3 which was the same as the notchback up front, but had a continuous slope from the roofline to the rear bumper. It looked both roomy and sporty. The car used the same body on frame setup of the other Type3s, and torsion bar suspension front and rear. It had a trunk front and rear, but they were rather shallow. Of course the engine was the same low profile air-cooled horizontally opposed 4 cylinder that served all of the Type 3 cars.IT used a 4 speed manual, although it was joined in the late sixties by an automatic. It appeared that VW had found another way to leverage the platform.
Although you have to put the performance into perspective for the time, the Fastback was not fast. It was light at around 1900 lbs, but it only had 44 bhp, and meandered from 0 to 60 in around 25 seconds. It had a top speed of about 80 mph. For what it was intended, a family car with more room than the Beetle, it was not bad. That was the premise of the TV commercial above featuring a young Dustin Hoffman. The car managed about 27 mpg, which was not great, but not bad either. It also had the same poor heating system that plagued the Beetle, so overall it was not the great successor that Europe had been eagerly awaiting.
In the US, the Beetle was still a very hot selling car, and Volkswagen, which was also facing capacity issues as it brought the new Emden plant online, delayed plans to import the Type 3. Many of the early cars that made there way to the US were gray market cars. In 1966, the Fastbacks arrived, and they did so into a market that seemed to be in love with the fastback concept. Mustangs, Corvettes, and Barracudas were all sporting fastback variations. It is fair to say that the VW was more Slowback than Fastback. In 1968 and 1969, three important upgrades were introduced, an automatic transmission, independent rear suspension, and Bosch D-Jetronic fuel injection. This is considered to be the first use of fuel injection in a volume production vehicle. These changes were popular in the US. In 1970 the fastback got some modest revisions to the nose, and then stayed in production until 1973 when the Dasher was introduced.