Heres the info for displacement. I used the specs they gave on https://www.diyaudioandvideo.com/Calculator/SpeakerDriverDisplacement/
Speaker Displacement
Effective Cone Diameter = 18 inMounting Depth = 10.1 inOne-way, Linear Excursion (Xmax) = 0.9 inMagnet Diameter = 7.35 inMagnet Height = 3.5 inFront Baffle Thickness = 0.75 inFlush Mount = NoDimensions
Driver Displacement = 0.24 ft3