From your last post, it sounds like you may need to change plug wires. GMPP sells sets and they are good, Mine on my truck, 88 454 TBI, measured like 300 to 500 ohms depending on the length. A great improvement.
Rotor cap carbon-tracked, happens when too much resistance is in line. Usually an open wire, very lean fuel mixture, too large plug gap, wrong material rotor made. Spark plug misfire under heavy dynamic compression.
The above will also burn out a coil, as it builds up too much heat from generating the spark needed.
Food for thought.......
Everett "OBJECTS IN THE MIRROR APPEAR QUICKLY UPON RAPID DECELERATION"