Originally posted by �¡ Se�±iorSiesta !:
Originally posted by projectSHO89:
Fine-wire plugs fire at a lower voltage threshold. This is a net reduction in power and slows the erosion of the ground electrode to a minimal level compared to a single plat plug that is firing the "wrong" direction.



Does this mean that the stock Contour coil pack will lower its voltage to accomodate the fine wire plugs?



You must not understand how a coil functions. This was part of what was taught on how to read a scope pattern when such equipment was in common use at repair shops.

There are two concepts to understand. Available voltage and required voltage. Available voltage is the maximum voltage that a coil can produce. Required voltage is the voltage required to fire a spark plug. Required voltage rises as the plug wears, becomes somewhat fouled, cylinder pressure rises, as fuel mixture become leaner, and when mixture become excessively rich to the point that the plug fouls.

When required voltage become greater than available voltage there is a missfire.

Lower required voltage to start with from improved plug design could be a good thing, leaving more coil reserve.

Jim Johnson 98 SVT 03 Escape Limited