frankwer, please elaborate. Even if the BF1's physics isn't finished (ie. not all aspects of physics relating to it are simulated), nothing was fudged thus far. That's what Niels is getting at.
As for the inertias, the matrix has this form:
[ I_xx, -I_xy, -I_xz ]
[ -I_yx, I_yy, -I_yz ]
[ -I_zx, -I_zy, I_zz ]
I assume rFactor just uses I_xx, I_yy and I_zz, you'll have to figure out which is which in LFS.