Frosty, When you built you injector what size did you drill the orifice? If I recall hammers was .035 mig tip. not sure if there is pros or con to a mig tip. it would be handy, but then again there is a lot of cool to made my own on the lathe. I will be building with a 3/4 pipe, and unless I come up with anything better, and this simple it will be the Hammer design. I will have 300 -350 cubic inches in the forge. Thanks for any input. And the info you gave Cary ( it is helping me also) Mark