[meford4u]

From what I have learned through my son as a mechanic in training and my father-in-law as a electrician, the quality of the wire and the size of the wires allows the current to run freely the larger the size of the wire. The stock wires on the Focus are restrictive to allowing current to run through the wires, creating a lower spark value for the spark plug. A larger coiled wire made up of several smaller wires coiled together is the best application for an electrical charge because this creates several pathways of little resistants.

This is how it was explained to me.