Since my memory is suspect about a few things I'm here for some help...I'm working on a particular set up and wondering what size the original petcock was for an Ironhead. I seem to remember 3/8" but maybe it was 1/4"? I also remember it as a single petcock not duals. Am I hallucinating eh? I'd like to run a single 1/4" but would it work with a stock mill?