An e-core coil is better than the stock coil, though I can't say exactly why. The stock coil could spark internally or perhaps it has different inductance to give a lower energy spark. The reason the 8-pin HEI module is better is that you can easily pair it with the GM coil, using their factory cable. If for some reason, you want to stay Mopar, you could use the e-core coil from a Magnum engine, but would have to fab your own cable (junkyard to get the mating connector too). It is mounted on the front bracket in Magnum engines.
