You're not quite asking the right question here. You don't want to know how armor and rating are related, you want to know why the Orange item hasIt's a higher rating at all, if it's got lower stats aside fromtypo on tooltip for the net 17 endurance.
The Orange item, as denoted by its color, supports item modifications in question.
You're right -Torhead reports the base item is a bit of a wash compared to the level 17 green.
But slot in an Armoring mod, a Mod mod, and an Enhancement modas having 307 armor, and then seewhich matches what comparing the stats again gets ya. It is a higher rank because it has the potential for having better stats - it's just that, due to their nature, Orange items require a bit more investment before they're up"Stat Changes" box would lead one to snuff.expect ( 228 + 79 = 307)
The system might alsoScuttlebutt says that this value will properly show up after you equip it, just be favoring the +17 stamina bonus - the system thinks 17 stamina is much better than 79 armornot before.