Molindar is a STR 16, CON 18 knight. He had Power Gloves and an Amulet of Strength (which I had him unequip). His carrying capacity is 2700 at this point. I had him load himself up with Meat (weight 10) and Candy (weight 1) until he was at 100%. He couldn't pick up a single piece of Candy. Thus we knew he was at his maximum capacity.

Then, I had him put on his Troll Belt (it was already in his inventory, so it was occupying 50 weight, but its effect was off). When he put it on, he went to 82%.

He then tried to pick up as much meat and candy as possible. The total meat picked up was 54. Thus, we can conclude that the amount of weight that a Troll Belt adds is 540. This is consistent with what he saw on his screen. If your capacity was boosted from 2700 to 3240 (2700 + 540 = 3240), that would make 2700 be 83.3% which is close enough to the reported 82%.

This hints that the conclusions we drew from the PlayForum article about the Belt of Titan are likely incorrect. There is no way Troll Belt adds 540 and Titan's Belt slows you and only adds 200. So, we're just going to have to wait until one of our fellow Lineage players gets the Titan's Belt before we can conclude anything.

So for now, the ways to increase your carrying are:

Next stop: Ogre's Belt.