When this reg came to me, it was pretty beat up and I had to use silicon to seal the top can to the body ring...
Well, that wouldn't do, so I have straightened the cans. I also wanted to maximize the performance when I added a a Phoenix and an HPR by boring out the passage between the 1st stage and the 2nd stage.
Someone else did this, but I cannot find the thread from several years ago. I plan to leave the volcano orifice alone, but is there a real advantage to boring out the air passage? I've gone up, in two steps, to 13/64.