Dis8-Chevy Distributorless Ignition System Small/Big Block Installation Manual

These instruction sheets are precise and accurate. They are designed to take you through the installation, step by step, in a logical sequence. If you follow them, the system will work the first time, every time. If you do not follow them, Cypress Engineering cannot guarantee the results. Due to the high-energy output of this system, only 8mm silicone spark plug wires, such as the ones available from Compu-Tronix, should be used.

High quality spark plugs, in new or good condition must be used. Spark plug gaps up to 0.045” may be used with this system. Use as large a spark plug gap as possible without inducing misfire. Never crank the engine with any high voltage spark plug wires disconnected from the coil pack terminals or spark plugs. This puts a very high stress on the coil and it is dangerous!
DO NOT try to time this system with a dial back timing light. Each spark plug wire conducts current once per engine revolution instead of once every other revolution as in a conventional system. Use only a standard timing light with a clamp on inductive type pick up.
TECH TIP: Verify timing settings before removing any existing ignition components.

WASTE SPARK IGNITION – OVERVIEW
The Compu-Tronix Distributorless Ignition System is a “waste spark” type ignition system. The spark events are controlled by the Mechanical Trigger Device and Electronic Control Module (ECM). The spark plugs are fired directly from a pair of high energy coil packs. Each coil pack has two internal coils making for a total of four coils. Each individual coil has two terminals that provide spark output to two cylinders. In a waste spark type ignition system, each cylinder is partnered with another cylinder that is phased 360° apart from it. This means both cylinders are at Top Dead Center (TDC) at the same time; one cylinder is at TDC compression while the other is at TDC exhaust. Each coil has two output terminals; one for each of the paired, out of phase, cylinders.

source