I find that if I get really close a bunch of times and manage to pull back from the edge, prolong that moment, it really seems to build up the pressure of it, and I can get some decent distance out of it once I finally let it happen. Also, I went thru some fertility treatments a few years ago, and a herbalist told me that some porn stars he counselled use high doses of Vitamin E to increase the size of the load. I did notice an increase, nothing on a Peter North level, but definitely more than I was used to.