The Bears celebrated the opening of their final season at Floyd Casey Stadium by taking a 28-0 lead in the first quarter after Nick Florence, last year's record-setting replacement for Heisman Trophy winner Robert Griffin III, delivered the pre-game prayer.
Petty, a junior, needed just 10 plays and 2:05 combined on game-opening drives of 70 and 65 yards for a 14-0 lead.
Wofford, one of the best running teams in FCS, struggled in its first game without all-time rushing leader Eric Breitenstein. Playing their first game in Texas, the Terriers needed 60 carries to get 173 rushing yards, 2.9 yards per run.
The game-time temperature was 102 for the start of the 64th season at Floyd Casey, which will be replaced next year by a campus stadium on the Brazos River.
The heat didn't bother the Bears, who surpassed what the school calls the modern era scoring record - a 68-13 victory against Northwestern State in 2009, the second season under coach Art Briles.
It was the most points for Baylor since an 88-0 victory against Stephen F. Austin in 1929.
Glasco Martin opened the scoring with an 8-yard run up the middle, and Antwan Goodley was waiting in the end zone and fell backward on the gold paint with the second touchdown after a brief juggle on a 27-yard pass from Petty.
The junior who backed up Griffin two years ago and Florence last season was 14 of 18 for 202 yards in the first half, which ended with the Bears in front 38-0.
Petty finished 18 of 23 without an interception, although he did lose a fumble when the ball was knocked out of his hand as he set up to throw.
Backup Seth Russell was 4 of 4 for 99 yards, including a 70-yard touchdown to Corey Coleman. The Bears never punted and rolled up 692 yards total offense.
Tevin Reese had five catches for 97 yards - including a 44-yard score from Petty - and Goodley added four grabs for 68 yards. Goodley also had a 22-yard run on the opening drive.
The first time Wofford stopped Baylor without a turnover, Aaron Jones broke the school record for field goals with the 46th of his career, a 25-yarder that put the Bears up 31-0.
Baylor President Ken Starr, the former independent counsel who investigated former President Bill Clinton's White House, led the students onto field before the game with a full sprint for 100 yards. Then he turned it over to Seastrunk, who set a school record with his fifth straight 100-yard game.
The former high school star from nearby Temple, who originally went to Oregon but returned closer to home after a redshirt season, scored from 7 yards in the first quarter and went 23 yards virtually untouched up the middle for a 38-0 lead late in the first half.
Two plays after Seastrunk's first touchdown, Baylor secured the eighth quarter of at least 28 points in school history when Chris McAllister batted a pass from Michael Weimer into the air, caught it and took the interception 25 yards to the end zone with nobody in front of him.
Wofford rotated three quarterbacks in Weimer, James Lawson and Evan Jacks but couldn't find much rhythm in its option-based offense. The results were worse when the Terriers tried to throw.
Baylor safety Ahmad Dixon delivered a crushing hit on Will Irwin after a short catch on the Terriers' second play. After McCallister's interception return, Weimer lost a fumble when he stumbled in the pocket and fumbled as he was hit. Baylor's Jamal Palmer recovered.
The Terriers got their only points on a 15-play drive to Kasey Redfern's 22-yard field goal in the third quarter.