More wisdom from Harry Schoell (from the steam car club forum): Harry schoell Re: Hi presure April 10, 2003 06:41PM Andy, what I am trying to do ,as in my original thread (searching), the higher the pressure the smaller the machine. At SC their is no control problems as you are dealing with a super heated fluid only. Multitubes present no problems. Tube burnout is no problem, no dry spots. I haven't heard a good reason why not . Please enlighiten me. I am designing and building test engines. They are very unusual and are a complete package. Should have been done by now, other enginering projects have taken up my time. Frustrating to look at half finished engines. thank y Whaddya think Tom? As long as you operate at supercritical pressure, there will be no tube burnout... "Should have been done by now" No kidding? "Frustrating to look at half finished engines." Do tell. But probably not nearly as frustrating as having invested money in them. Hey! There's the answer! Cyclone needs to change its motto from "One world, one engine" to "Frustrating to look at half finished engines."