Provided you didn’t disable automatic settings in the vorpX config app, Far Cry 3 has fully automated Direct VR field of view since quite a while which is adjusted perfectly to fit your headset. The same is true for Far Cry 1, 2, 4 and Primal, also Battlefield 3, 4 and 1.
For games that do not have that please check the “Essential Game Hints” guide in the vorpX help. It explains which options you have to either solve or circumvent FOV related issues in cases that vorpX cannot handle automatically.