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TR2/3/3A Distributor Cap resistance

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BobbyO

Jedi Hopeful
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Can anyone tell me what the resistance should be when measuring between the plunger in the distributor cap that contacts the rotor and the screw that attaches the coil wire? I have several distributor caps and it seems they all have different resistances when measured at this location, differences being from tens of ohms to thousands of ohms. What's correct?
 
I've noticed that too, with other cars; some caps have a fairly high resistance, and some next to nothing. It's surprising.

Given that resistor ignition wires have something like 10,000 ohms of resistance, I wouldn't worry about even a few thousand in the distributor cap.
 
Thanks Steve. Hadn't thought about the resistance of resistor ignition wires. Have a local friend with a '62 TR3B so I measured his and it was around 28 ohms so I'm using the cap with about the same although I have three others that measured in the 10-12K ohm region and one that is in the 200 ohm area.
 
That button is supposed to be a suppression resistor, so I'm thinking that 28 ohms is not right. But if you've got resistance somewhere else (like in the wires or plug caps), then it probably doesn't matter much.
 
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