While there have been scattered posts about the X frunk capacity compared to the S, I haven't seen anyone attempt to calculate the size differences. The S specs page at Model S Specifications | Tesla Motors states "Front trunk cargo volume 5.3 cu ft". It does not state if that is for the Dual Motor or RWD cars. Searching for Model S reviews online from 2013 shows that same figure was reported, so that tells me that the 5. 3 cu. ft. is for RWD cars. For example, see How Much Space IS There Inside A 2012 Tesla Model S Anyway? Dual Motor S cars have a significantly smaller frunk. The X specs page at Model X Specifications | Tesla Motors does not appear to show a frunk volume figure. In another thread the dimensions were posted: 44L X 15-18W x15H. Assuming an average width of 16", the volume calculates out to about 8.3 cu. ft. So the X frunk appears to have over 50% more capacity than the RWD S frunk, and likely about double the capacity of the Dual Motor S frunk. Corrections to my data are welcomed.