Screamin' Sasquatch is a 1929 Waco Taperwing operated by John Klatt Airshows that features a Pratt & Whitney 985 Wasp Junior and a GE J-85/CJ-610 turbojet (used in the Air Force T-38). The two engines provide a combined 4,500 lbs of thrust to an aircraft weighing only about 4,000 lbs. You do the math.
Surprisingly, this isn't the first Waco with a jet strapped to its belly. Jimmy Franklin put the same combination of engines on his Waco "Mystery Ship" in 1996 and performed with it until he was tragically killed during an airshow in 2005.