Re: HEI problem - pickup coil
Magnetic pickups for HEI are available in two different ways.
One is the coil itself, the other is a complete assembly, case, coil, magnet, outer armature, screws. I have had a few HEI magnetic pickups go bad.
Dave Ray showed me a tool he made to align the outer armature when taking the pickup apart to replace just the coil, It's plastic, fits into the top bushing and aligns the armature centered. He says he's seen a lot of HEI's that lost spark at low speed on 4 cylinders, gained them back in the mid range, then lost the other 4 on top end rpms. On every one of them, when he aligned the pickup, the distributor worked properly again. All the ones that dropped cylinders had the outer armature out of alignment, sometimes striking the inner on 3 or 4 of the teeth.
His advice, the best way to replace a magnetic pickup is to just buy the one that is completely assembled, and pre-aligned. The ones I have purchased are only about a dollar more for the complete pickup assembled, over just the coil itself.