It is technically possible for three teams in one conference to have perfect seasons.
The 1972 Miami Dolphins went 14-0 in the regular season. The 2007 New England Patriots went 16-0 in the regular season.
The 2008 Boise State football team ended up with a 12-1 record and were WAC champions for the 6th season in 7. They went undefeated in Conference play and the rest of the 'regular season'. Their only loss was to TCU, 17-16, in the Poinsettia Bowl.
The 1972 Miami Dolphins are the only team to go through a season undefeated. Their regular season record was 14-0 and they won their two conference playoff games and the Super Bowl to wind up 17-0.
As of June 2014 Barry Bonds holds the record for most regular season homeruns. The record is 73 which beat Mark McGwire's record.
From 1933 through 2013, the Pittsburgh Steelers have a regular season record of 569-519-20.
Chicago bulls
The 1972 Miami Dolphins went 14-0 in the regular season. The 2007 New England Patriots went 16-0 in the regular season.
Their regular season record in 2007 was 10-6
The Ivy League also sends the regular season champion, as the conference has no tournament to end the season.
The 2008 Boise State football team ended up with a 12-1 record and were WAC champions for the 6th season in 7. They went undefeated in Conference play and the rest of the 'regular season'. Their only loss was to TCU, 17-16, in the Poinsettia Bowl.
In 2004, the Steelers had a 15-1 regular season record.
The Cowboys 2007 regular season record was 13-3.
Their regular season record for the 2009-2010 football season was 13-3.
The Packers final record for the 2006 regular season was 8-8.
The Redskins regular season record in the 2006 NFL season was 5-11.
In 2005 when the Steelers won the Super Bowl, their regular season record was 11-5.
The Cowboys record was 10-6 in the 1996 regular season.