RSS Importer - Feed Frequency?

[davemackey]

So, I want to comment out the code in the rss feed importer that checks whether the rss feed has recently been checked - mainly b/c it can only go down to a minimum of an hour (at least as far as I can tell). However, I've looked through all the RSS Importer code and don't see where the code checks to see if a feed was updated within x period and skips it if so. Can anyone point me to this code so I can edit it and have the Importer always check for new stories from RSS feeds? Thanks.
David.