Sounds like a bad tune toasted your motor.

 

x2

 

How many engines do you laying around now? Didn't you have a 5four, but bent the valves when the timing got messed up. Then you got another ? Not sure what happened with all that, you stopped posting. ? You might be able to put together one good one out of the lot. Just make double sure the timing gets set right and load your factory tune.