A while back, Cliff mentioned he had never heard of excessively rich fuel/air mixtures causing exhaust backfires. Well, check out the attached photos.
This occurred a couple years ago while attempting to use a JEGS "remanufactured" Q-jet before I learned they are junk. This unit had obvious issues; the idle was terribly rich, even with the screws fully seated, and my engine was only able to run on about 5 cylinders.
Apparently this filled my exhaust system with an explosive mixture of fuel and air, because as soon as I touched the ignition to re-start the engine, there was a deafening BANG from the exhaust.
