Evaluation of Dual Output Ignition Coil (Mike’s XS)

Date: Dec 20, 2008
Location: Rock Hill, SC

Ambient Temperature: 60 F
Humidity: 93%
Barometric Pressure: 29.93

Coil Number 1:

Coil Description: Dual output 12VDC coil designed for motorcycle applications.
Manufacturer: Unknown
Primary resistance spec: Unknown
Primary resistance measured: 3.3 Ohms @ 60F
Secondary resistance spec: Unknown
Secondary resistance measured: 15 K Ohms @ 60F

Source Test Voltage: 12.5 VDC
Driver: PAMCO Model 1001 Hall effect, IGBT output transistor.
Transistor saturated voltage: 1.2 V
Effective voltage to coil: 11.3 VDC
Dwell Angle: 90 Deg (Coil fires twice per camshaft revolution)
Duty cycle: 50%

Test Setup 1:

PAMCO driver rotor rotated with a continuously variable motor / chuck to produce equivalent operation of a camshaft at ambient temperature. Coil connected to two NGK BP7ES spark plugs through a NGK 5K Ohm caps.

Observations with .028 plug gap: Spark intensity was high and of excellent quality.

Observations with .040 plug gap: Spark intensity was high and of excellent quality.

Test was continued for a period of 1 Hour. Temperature of the coil increased to 112F.

Test Setup 2:

Spark plugs and caps were removed and the output wires from the coil were placed end to end. Initial gap between wires was set to 1.0cm, which is equivalent to 30 Kv. Arc was produced between the ends of the wires with the above test setup.

Test Setup 3:

Spark plugs and caps were removed and the output wires from the coil were placed end to end. Gap between wires was set to 1.5cm, which is equivalent to 45 Kv. Arc was produced between the ends of the wires with the above test setup.

Test Setup 4:

Source voltage was increased to 14VDC. Gap between wires was increased to 2.5 cm which is equivalent to 75 KV. Arc was produced between the wires.

Conclusion:

The test coil is of excellent quality and capable of producing up to 75 Kvolts of voltage @ 14VDC.