Reply to "351C Engine parts-detailed plan"

Thats the one! Thin layers of coiled steel don't take shock-loads well and progressively crack the layers. Worst case is when only the load-side cracks and the gear rotates about 20 degrees retarded but still allows the engine to run (poorly). Retarded timing from this will drive one crazy trying to find the cause- damage is only visible if you pull the distributor and look at BOTH ends of the pin. One end may be missing. The cracked pieces are down in the pan waiting to destroy the pump or extension shaft- maybe both. Mallory, Accell and several other mfgrs all use the same undersized stock pin.