For purposes of our discussion here, there are two different types of
distributorless ignition systems (DIS):
Coil On (or Near) Plug Ignition - As the
name implies, there is a coil for each cylinder in the engine. To know which
cylinder is firing, both cam and crank timing signals must be received by the ECU.
Waste-Spark Ignition - These can usually be identified by the
two-tower coils. The beauty of waste-spark ignitions is that they do not require
cam timing synchronization. But because they rely on the crank timing only, they
fire two cylinders at once. One is fired in the compression cycle and the second
is fired during the exhaust cycle. Since only one of the two are actually being
fired into an air/fuel mixture, the term "waste spark" is given. UPDATE: As of January 2019 Holley has discontinued all Waste Spark ignition systems. Only replacement components remain available.
Holley's present ignition focus is on their really fantastic Smart Coil.
By coupling 8 of these coils with the Smart Coil Harness,
you have an essentially plug-and-play high performance coil set for the GM LSx engines.
Adding the Universal
COP Ignition Harness allows you to connect that to any of the standard Holley EFI
main harness ignition connectors. This means you can have COP DIS on virtually
any 4-, 6-, or 8-cylinder engine running a Holley EFI ECU (provided you have a cam sync
signal, as mentioned above.)
For most applications, a very slight benefit is achieved in Coil On Plug (COP)
ignitions. True, the Waste Spark (WS) ignition is wasting a bit of energy by
firing into two cylinders, but the coil is typically a bit larger than the normal COP
ignition to compensate for that. And for those individuals who have no source of
cam timing signal on their engines, the benefit is hardly worth the effort of
engineering a working cam timing signal (particularly if fully-sequential fuel
injection is not required.)
Holley originally was all-in on the concept of WS DIS. But as techhnology
advanced (along with customer expectations) very few WS DIS were being implemented.
At the time of this writing, Holley has discontinued their 4-, 6-, and 8-cylinder
WS DIS. A limited amount of stock remains. Once sold, a WS DIS can still
be achieved by purchasing coils, sensors, and harnesses separately. It will
require a bit more custom wiring. Contact us for pre-sale engineering
assistance.
The WS DIS kits below require the installer to obtain a Trigger
Wheel (sold separately) and mount it and the hall effect sensor (included in
the kit.)
Choose From:
Coil Per Plug DIS Kits-
Coil Per Plug DIS Components -
If you are planning on running coil-per-plug ignition and haven't already committed
to a crank and cam sensor setup, make the smart choice and choose a Holley Dual Sync Distributor to provide
your crank and cam sync. Order yours with the smooth-top distributor cover for a
clean, finished look!
Waste Fire Replacement Components -
+
+
+
+
