Actually, during the late 1970's Boeing seriously looked at designing a 727-300 that dispensed with the three JT8D engines in favor of two PW2037 engines. If that project had gone ahead it would have likely cause Airbus to lose a lot
of A320 orders because airlines like IB
would have bought this plane en masse
for parts commonality reasons and Boeing would likely have kept the 727 line going even today!