In 1970, the 1701 cc BDB was created for the Escort RS1600, and this engine received fuel injection for the first time in the series as 1701 cc BDC. Two years later, the BDA series was adopted for Formula 2; first came the 1790 cc BDE, then the 1927 cc BDF eventually reaching a maximum of 1975 cc BDG in 1973. As the bore size reached ever closer to the bore centre distance, leaving little space in between cylinders, the all three types had brazed-in cylinder liners to the block. As a departure from the Ford iron block, the BDG received a new aluminium block (originally designed by Brian Hart in 1971 and re-engineered by Cosworth) soon after, and this cylinder block was used as a replacement part in rebuilding many other BD series engines as well as some Mk.XIII engines.