Here is a link to a helix calculator. With this link you can not only calculate helix problems, but scale speed and distance. I am offering this link as a layout planning tool: http://nietzsche.mit.edu/auro/trains/tech/HELIX/
Excellent timing. Have added this to my bookmarks. I was just about to attempt some calculations for my empire planning. Boxcab E50
thank you. I think. Or is it time for me to go back to my first N scale layout - a Kato unitrack oval?