IDE connectors have 40 pins. Original (40 wire) IDE cables had 40 signal wires. Modern high speed (40 pin/80 wire) IDE cables have an extra screening wire between each adjacent pair of signal wires. These 40 extra wires are not connected to any of the pins.
Your engineer sounds confused, as there are no 80 pin IDE drives, only 80 wire IDE cables. However, some SCSI drives have 80 pin SCA connectors.