Trying to Balance the Scale

I'm trying to balance the weights so to speak regarding my Suprapubic (SPT) and Stoma. I have to have the majority of the urine come out of the Stoma side since that is what I will be using the get the urine output for the rest of my life. I just can't get it to happen. The SPT is a 20 french foley and the surgeon has me cathing with a 14 fr catheter. That would make sense why most of it is coming out of the SPT. When I had my neobladder I was never allowed to go below a 16 fr and when I had a foley in it had to be an 18 fr foley. There were two reasons for this, first my urethra was closing up and my doctor feared that if I used anything smaller than a 16, that it would just close off on me. Second I tend to have much more mucous than the average persoon even years after the surgery so in order to get all of it out I needed a larger catheter. So I am thinking the same would be true for this case too. The holes on the 14 fr are soooooooo small. My surgeon told me I could try a 16 way back when he was teaching me to catheterize but that was over a week ago. I don't want to use the 16 without permission from him or my local urologist because I don't want to create any damage. The tract may have been made to accomodate a certain size. But by staying with the 14 fr I am not getting enough out compared to the SPT side which is a 20 fr. I don't know what to do but wait until I see my local urologist on Tuesday and ask him if a 16 could be used on this new stoma and if so does he have any. My out put has basically been about 50/50, there are a few times I will get more out of the Stoma side but still a lot comes out of the SPT even after that. I have recorded all of it and I still am recording it. But until the scale weighs in favor of the stoma, I have to leave this damn SPT in for my anniversary.