There is an impression amongst motorists that when a car is fitted with a sports coil the gaps at the plug points must be opened wider than normal. The Lodge plugs company, however, point out that this is not so; so long as the plug gaps themselves are normal it is immaterial whether the coil is of the sports or standard type. If, however, it is desired to use wider plug gaps, then a sports-type coil is advisable, if not essential.
The main object of installing a sports coil is to provide the necessary higher voltage current to jump wider plug gaps for the purpose of igniting weak or otherwise special gas mixture, which a normal spark gap might not be able to cope with. Alternatively, the higher voltage coil will provide a spark across the normal plug gap in a high compression engine where an ordinary coil might fail.
Another advantage of a sports coil is that it will compensate for a partially run-down or otherwise sub-standard battery which might be unable to produce the necessary spark with an ordinary coil. An example of this is found when starting from cold in the winter. The use of the starter then takes so heavy a load from the battery as substantially to reduce the voltage for ignition purposes. In such circumstances a sports coil will often make all the difference between “Stop” and “Go.”