A good source is Statfox . Go to http://www.statfox.com/mlb/mlbteam.asp?teamid=SAN+DIEGO&season=2005 , and scroll down to Situational Breakdown Summary near the bottom, as you'll see this season so far San Diego is 4-6 on Overs Unders (4 overs, 6 unders) at home, so obviously that would be the record so far for their homepark.