I have not much luck with the cap tube system. my latest one, i had to change both. Length of the cap tube is as recommend by the manufacture and larger capacity filter dryer. not working so good. so I cut the cap tube few inches shorter than was told to get a better result.
My experience with cap tube systems has been that if the liquid line dryer is upsized, the charge usually has to be increased to compensate. The larger drier increases the internal volume of the system. Also, I liked to angle the dryer outlet down towards the cap tube entrance.