The A7 was the team's first time running a turbocharged engine. This was the same powerful BMW M12Straight 4 which was also used by the Brabham team, though unlike Brabham who had BMW engineers looking after their engines, the Arrows engines were maintained and developed by Swiss engine guru Heini Mader. This left Arrows with around 800 bhp (597 kW; 811 PS) while the factory units were developing around 900 bhp (671 kW; 912 PS)
in the 9/1984 Sport Auto they found the Arrows A7 had a performance of: