I'm looking for a site that can calculate optimal pacing for a goal race depending on the course. I would like this for my next race, the Brussels Half-Marathon. So far, the closest thing I've found (and it's pretty cool, in my view) is this: http://www.pacecalculator.com/#gen-course
Only problem is you can only pick one of their courses (and Brussels is not included). Do you know of a similar tool where uploading a new course is possible?