A while back I bought a copy of Dyno2000 from Motion Software (www.motionsoftware.com). It seemed like it might be a realitively inexpensive way to try some things without the associated time and expense of doing them for real. It has been great fun playing with the program but I don't know if it really means much. Has anyone else tried this, or any of the other engine simulation programs? Comments (need I ask!)?