The car was roughly the same size as the dreaded Audi V8, but lacked the power and four wheel drive traction to keep up. Owing to Group A’s strict homologation rules, Opel had no way of bringing the car up to speed without building a dramatically expensive road car as well. In the much looser environment offered by FIA Class 1 however, this was no longer an issue.
As the war progressed, military authorities placed greater stress on the development of air-cooled engines, which they felt had more immunity to damage from weather, shellfire, and misuse. To meet this demand, Opel engineers developed an unusual variation on normal cooling for the 3.6 L truck engine. It was called "air-oil cooling", and used engine oil to take heat away from the jackets around the cylinder barrels. The heads were directly cooled by air, there being three separate aluminium finned heads, each serving two cylinders. Of this interesting engine, which developed 72 hp (54 kW; 73 PS) at 3,000 rpm on 74-octane fuel, only three examples were built.
In Australia, the car was launched to much fanfare from many motor journalists, and went on to win the Wheels 2001 "Car of the Year" (COTY). Holden also imported the SRi version with the 1.8L Astra motor and uprated sports suspension including traction control, ABS brakes, a better tyre/wheel combination and Irmscher body kit to produce a "baby hot hatch" Barina.
While the Ipanema clearly succeeded the Marajó, production of the Chevette (by now in sedan form only, the hatchback having been discontinued after the 1987 model year) and of the Kadett noticeably overlapped; the newer model was placed above the old one in Chevrolet's lineup. While Chevrolet entertained the possibility of a pick-up version of the Kadett E, it never materialized.