I put a 429 in a 78 F150 4X4, w/C6. Ran great. Changed the distributor and ecm to units for a 460.

Problem: Keeps acting like it jumps time, backfires and blows out the ecm.

I have replaced the distribuitor 3 times and the ecm 4 times.

Any suggestions on what is going on??????

Would greatly appreciate some info.

Thanks

 

I would look at your wiring harness sounds like something is shorting out to me, not a problem with the engine.
on edit: when you put the engine in did you put a ground strap from the engine to the frame, or run the ground from the battery to the engine, and frame. A ground can cause all kinds of problems, and then look at your wiring harness like I said.