One coil per cylinder allows the coil a longer time to accumulate a
charge between sparks, and therefore a higher energy spark. This is a
very popular design and is easily adaptable to different engine layouts.
Plug Top Coil
The plug top coil is mounted directly on the spark plug and each unit
is powered separately to allow the engine to independently manage each
coil. Plug top coils are also used where a spark plug well diameter is
too small to allow for a pencil coil (22mm).
Are 4 or 2 coils mounted together that fit directly on top of the
engine. In the four coil configuration they operate in a similar way to
pencil and plug top coils. In the 2 coil configuration they operate a
wasted spark system where each coil links to a pair of cylinders,
normally 1- 4 and 2- 3. This means that one plug will be sparking during
the end of the exhaust stroke while the other plug fires at the usual
time at the end of the compression stroke.
These are near plug coils which normally operate the wasted spark
system of 1 coil to 2 cylinders. The pack design can offer one of the
highest energy densities to enable a mass reduction of up to 40 percent
compared with conventional ignition coils. Integrated Coil & Wire
set The ignition coil and wire set come as one complete unit. This
allows for the coil to be placed away from the spark plugs because of
lack of space or hostile surrounding while decreasing the chances of a
poor connection between the coil and plug.