18-06-2024, 06:41 PM
Hi
The simple answer is no, the ignition points condenser can't be replaced by a varistor (voltage dependent resistor).
To give more detail, the ignition condenser's main job is to temporarily store energy from the coil immediately after the points open, which is then rapidly released back as useful energy into the ignition system. A varistor would just turn it into heat, and reduce the spark energy. The condenser and the coil primary inductance form a resonant system. The resonance frequency is not ultra critical, and although the normal condenser value is 0.2 microfarads I have found only a small reduction in performance with 0.1 or 0.4 microfarads. A beneficial side effect of the condenser is a considerable reduction (but not complete elimination) of the arcing at the points.
I should say at this point that as I have never actually tried a varistor across the ignition points I can't be 100% certain of the above - maybe someone of enquiring mind could try it and report back !
The simple answer is no, the ignition points condenser can't be replaced by a varistor (voltage dependent resistor).
To give more detail, the ignition condenser's main job is to temporarily store energy from the coil immediately after the points open, which is then rapidly released back as useful energy into the ignition system. A varistor would just turn it into heat, and reduce the spark energy. The condenser and the coil primary inductance form a resonant system. The resonance frequency is not ultra critical, and although the normal condenser value is 0.2 microfarads I have found only a small reduction in performance with 0.1 or 0.4 microfarads. A beneficial side effect of the condenser is a considerable reduction (but not complete elimination) of the arcing at the points.
I should say at this point that as I have never actually tried a varistor across the ignition points I can't be 100% certain of the above - maybe someone of enquiring mind could try it and report back !