Ohms Law
Before attempting to understand the ignition system of an engine it is important to have an understanding of basic electricity principles.
Ohms law says that a pressure of one volt (E) will force a current (I) of one amp through a resistance of one ohm (R). In other words:
E = I*R
Amperage (I) and resistance (R) are directly proportional to voltage (E). If amperage or resistance increase then voltage will also increase.
An ignition system of an engine usually requires a minimum of 10,000 to 12,000 volts to create a sufficient arc across the spark plug air gap which ignites the air/fuel mixture.
a stock ignition coil generally provides 20K-30K volts aftermarket versions can provide 45K plus volts
To obtain that high of voltage a coil of wire is used to increase resistance which directly increases voltage.
https://www.pontiacdiy.com/how-to-improve-pontiac-v-8-engine-performance-ignition-guide/
How Electricity is Produced
If a wire is passed through a magnetic field an electrical current will flow on the wire. A larger wire or a larger number of wires that are passed through a magnetic field will increase the amount of current.
If current flows on a wire a magnetic field is produced around the outside of the wire.
Resistance (R) can be used to reduce the current (I) and increase the pressure or voltage (E).
In a small engine the magnet is located on the outer edge of the flywheel and the coil of wires is in a stationary position outside of the flywheel. The magnet passes by the coil with each revolution of the flywheel creating electricity on every revolution.
http://www.donzig.com/tech.html
Magneto Ignition (Simplified Explanation)
http://www.jegs.com/VendorInfo/Vertex/vertex.pdf
The ignition system consists of two circuits, a primary circuit and a secondary circuit. The primary circuit is consists of larger gauge wire windings in the coil, the primary coil wire, breaker points, and condenser (breaker points and condenser may be replaced by an electronic ignition module). The secondary circuit consists of smaller gauge wire windings in the coil, secondary wire from the coil, and the spark plug. The ratio of windings in the coil uses Ohm’s law to multiply the voltage. The ratio of secondary windings to primary windings is 60 to 1. Figure 1 diagrams both circuits. The coil only has two wires inside it, the primary wire and the secondary wire. Both wires are wound or coiled several times to increase resistance. The two wires are insulated from one another. One end of the primary wire is grounded to the engine block and the other end carries current to the breaker points and condenser. One end of the secondary wire is also grounded to the engine block and the other end carries current to the spark plug.
Current is produced in the primary circuit from the flywheel magnet passing through the primary windings of the coil. If the primary windings are carrying a current that produces a magnetic field around them which produces electricity on the secondary windings when the breaker points open and suddenly stop the flow of electricity on the primary circuit. The voltage is much higher on the secondary circuit due to the ratio of windings. The voltage produced on the secondary circuit is carried by the secondary wire to the spark plug. An arc is created between the contact points of the spark plug to ignite the air/fuel mixture.
Current is produced in the primary circuit from the flywheel magnet passing through the primary windings of the coil. If the primary windings are carrying a current that produces a magnetic field around them which produces electricity on the secondary windings when the breaker points open and suddenly stop the flow of electricity on the primary circuit. The voltage is much higher on the secondary circuit due to the ratio of windings. The voltage produced on the secondary circuit is carried by the secondary wire to the spark plug. An arc is created between the contact points of the spark plug to ignite the air/fuel mixture.
pontiac
http://www.boxwrench.net/specs/pont_265-455.htm
chevy sb
http://www.boxwrench.net/specs/chevy_sb.htm
chevy BB
http://www.boxwrench.net/specs/chevy_bb.htm
426hemi
http://www.boxwrench.net/specs/hemi_426.htm
383-440 mopar
http://www.boxwrench.net/specs/bchrys_B.htm
318-340-360 mopar
http://www.boxwrench.net/specs/schrys_A.htm
ford 429-460
http://www.boxwrench.net/specs/ford_429-514.htm
302-351 windsor ford
http://www.boxwrench.net/specs/ford_302_351W.htm
351 cleveland ford
http://www.boxwrench.net/specs/ford_351C.htm
352-428 ford
http://www.boxwrench.net/specs/ford_352-428.htm
Magneto Ignition
A magneto in a sense consists of two simple circuits, one called the primary circuit and the other the secondary circuit. Both Circuits have windings or coils which surround the same iron core and the magnets in the flywheel or rotor act on both circuits. Current can be induced in each by changing the magnetism in or around the coils of the circuit.
The primary circuit has relatively few turns of heavy wire (low resistance) and the circuit includes a set of breaker points and a condenser, or an electronic switch.
The secondary circuit has a coil with many turns of lighter wire (high resistance) which are wound around the outside of the primary winding, and includes a spark plug. There are about 60 turns in the secondary to each turn in the primary.
Before attempting to understand the ignition system of an engine it is important to have an understanding of basic electricity principles.
Ohms law says that a pressure of one volt (E) will force a current (I) of one amp through a resistance of one ohm (R). In other words:
E = I*R
Amperage (I) and resistance (R) are directly proportional to voltage (E). If amperage or resistance increase then voltage will also increase.
An ignition system of an engine usually requires a minimum of 10,000 to 12,000 volts to create a sufficient arc across the spark plug air gap which ignites the air/fuel mixture.
a stock ignition coil generally provides 20K-30K volts aftermarket versions can provide 45K plus volts
To obtain that high of voltage a coil of wire is used to increase resistance which directly increases voltage.
https://www.pontiacdiy.com/how-to-improve-pontiac-v-8-engine-performance-ignition-guide/
How Electricity is Produced
If a wire is passed through a magnetic field an electrical current will flow on the wire. A larger wire or a larger number of wires that are passed through a magnetic field will increase the amount of current.
If current flows on a wire a magnetic field is produced around the outside of the wire.
Resistance (R) can be used to reduce the current (I) and increase the pressure or voltage (E).
In a small engine the magnet is located on the outer edge of the flywheel and the coil of wires is in a stationary position outside of the flywheel. The magnet passes by the coil with each revolution of the flywheel creating electricity on every revolution.
http://www.donzig.com/tech.html
Magneto Ignition (Simplified Explanation)
http://www.jegs.com/VendorInfo/Vertex/vertex.pdf
The ignition system consists of two circuits, a primary circuit and a secondary circuit. The primary circuit is consists of larger gauge wire windings in the coil, the primary coil wire, breaker points, and condenser (breaker points and condenser may be replaced by an electronic ignition module). The secondary circuit consists of smaller gauge wire windings in the coil, secondary wire from the coil, and the spark plug. The ratio of windings in the coil uses Ohm’s law to multiply the voltage. The ratio of secondary windings to primary windings is 60 to 1. Figure 1 diagrams both circuits. The coil only has two wires inside it, the primary wire and the secondary wire. Both wires are wound or coiled several times to increase resistance. The two wires are insulated from one another. One end of the primary wire is grounded to the engine block and the other end carries current to the breaker points and condenser. One end of the secondary wire is also grounded to the engine block and the other end carries current to the spark plug.
Current is produced in the primary circuit from the flywheel magnet passing through the primary windings of the coil. If the primary windings are carrying a current that produces a magnetic field around them which produces electricity on the secondary windings when the breaker points open and suddenly stop the flow of electricity on the primary circuit. The voltage is much higher on the secondary circuit due to the ratio of windings. The voltage produced on the secondary circuit is carried by the secondary wire to the spark plug. An arc is created between the contact points of the spark plug to ignite the air/fuel mixture.
Current is produced in the primary circuit from the flywheel magnet passing through the primary windings of the coil. If the primary windings are carrying a current that produces a magnetic field around them which produces electricity on the secondary windings when the breaker points open and suddenly stop the flow of electricity on the primary circuit. The voltage is much higher on the secondary circuit due to the ratio of windings. The voltage produced on the secondary circuit is carried by the secondary wire to the spark plug. An arc is created between the contact points of the spark plug to ignite the air/fuel mixture.
pontiac
http://www.boxwrench.net/specs/pont_265-455.htm
chevy sb
http://www.boxwrench.net/specs/chevy_sb.htm
chevy BB
http://www.boxwrench.net/specs/chevy_bb.htm
426hemi
http://www.boxwrench.net/specs/hemi_426.htm
383-440 mopar
http://www.boxwrench.net/specs/bchrys_B.htm
318-340-360 mopar
http://www.boxwrench.net/specs/schrys_A.htm
ford 429-460
http://www.boxwrench.net/specs/ford_429-514.htm
302-351 windsor ford
http://www.boxwrench.net/specs/ford_302_351W.htm
351 cleveland ford
http://www.boxwrench.net/specs/ford_351C.htm
352-428 ford
http://www.boxwrench.net/specs/ford_352-428.htm
Magneto Ignition
A magneto in a sense consists of two simple circuits, one called the primary circuit and the other the secondary circuit. Both Circuits have windings or coils which surround the same iron core and the magnets in the flywheel or rotor act on both circuits. Current can be induced in each by changing the magnetism in or around the coils of the circuit.
The primary circuit has relatively few turns of heavy wire (low resistance) and the circuit includes a set of breaker points and a condenser, or an electronic switch.
The secondary circuit has a coil with many turns of lighter wire (high resistance) which are wound around the outside of the primary winding, and includes a spark plug. There are about 60 turns in the secondary to each turn in the primary.
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