Along with the other calendars I've setup (F1 and WGI) for sharing/import into Google Calendar, I've just now created another new one. This one is for SCCA Pro Racing's World Challenge series. And similar to my WGI calendar, this includes the event dates with just a location.
There are no specific details on the daily schedules and really, nothing more than the World Challenge website offers - but this can at least be imported to whatever calendaring program you use.
So... here we go... here's what the schedule looks like (you may need to scroll down within the window if you don't see any events):
And here are the separate formats you can download/import/whatever into your own calendar. You can get it in XML, iCal, and HTML flavors.
If you have any issues or problems with this calendar or want to report a change, please feel free to leave a comment. I'll do my best to keep it updated if the series changes theirs.