There were two distinct generations of the Kadett B: 1966-1967, and the 1968-1973. Bob Lutz had a hand in the key feature that distinguished the two. The torque-tube/leaf-spring rear suspension was replaced for 1968 by a coil-spring and control-arm set-up, designed to both improve ride and handling, especially in reducing the Kadett’s tendency to tippiness. Bob had recently arrived at Opel, where he mentioned that the Kadett had a bit of a rep in the US for being a bit tippy, especially in a J-turn maneuver. The engineers told him that the new rear suspension (seen here in this picture) would eliminate that, and invited him to see for himself. The result is self-evident (full story here).
The Buick Regal is a rebadged Opel Insignia. The main differences are the modified radiator grill and the altered colour of the passenger compartment illumination (blue instead of red). The Regal GS is comparable to the Insignia OPC. It was first assembled alongside the Insignia at the Opel plant in Rüsselsheim. Since the first quarter of 2011, it is now being built on the flexible assembly line at the GM plant in Oshawa, Canada.
The plucky Kadett B. I am still daily driving a 1100 sedan here in southern CA. Simple basic trouble free comfortable transportation. It does its job without fuss or pretentiousness. I am amazed at how well the engineers made a cheap car so useable without feeling as if you were in a penalty box. They just have a certain feel that I find appealing. *
Opel campaigned the car extensively in motorsport too. The rally version was uncompetitive, but Opel eagerly waded into the 160mph traffic jam that was the International Touring Car Championship. The ITCC was created from the German DTM series, in which Opel had struggled. A rule change allowed Opel to use a new 480bhp V6 derived from the road car. The resultant four-wheel-drive monster carried Manuel Reuter to the 1996 ITCC driver's crown and Opel won the manufacturers' gong, beating Alfa Romeo and Mercedes-Benz. It was the Calibra's finest hour.
The GSi's engine mapping had been carried out by Opel tuning specialists Irmscher. A model with the 82 PS (60 kW) 1.4 L multi point fuel injected engine, which was otherwise mechanically identical to the GSi, also became available as the Nova SRi in the United Kingdom. In January 1988, a turbocharged version of the Isuzu diesel engine was introduced, with power increased to 67 PS (49 kW).