Resistor Caps vs Plugs

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bpatton

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Does anyone know if resistor plugs satisfy the requirement served by resistor caps when used with electronic ignition?
 
As long as you have the resistance it shouldn't matter in which component.
 
Sure, plenty of them. Go to http://www.sparkplugs.com (for example) and you can find a cross-application chart. I use Denso IW-22s (fine-wire iridium) myself but anything that cross-references (to NGK BP7ES) will work.
 
Bob,
This is what Boyer said to the same question.

using resistor-equipped spark plugs should be just as effective as resistor plug caps. A value of 5000 ohms would be sufficient.
Click to expand...

Cash
 
This is good news. I don't trust resistor caps. I had one go open short on me once. Cooked the Accel coil and stranded me. In the middle of the desert. Met some great people in the process, but still..
 
Oddly enough the same thing happened to me on an old BMW. This is why my preference is now for two coils. Better to come home slowly thump thum[ thump than to walk.
 
cash said:
Bob,
This is what Boyer said to the same question.

using resistor-equipped spark plugs should be just as effective as resistor plug caps. A value of 5000 ohms would be sufficient.
Click to expand...

Cash
Click to expand...

Sparx said the same thing in response to my question about their three-phase alternator (which also requires 5K ohms resistance). Seeing's how it's getting difficult to find NON-resistor plugs (sure, there are still some, like NKG's BP7ES, a fine plug, but the selection is limited), I run low-resistance wires and resistor plugs.
 
What is the requirement for resistor plugs with regard to electronic ignition....this is a new one for me? I have a Lucas RITA ignition, use copper plug wires and NGK BP7ES or Champion N7YC plugs.
 
illf8ed said:
What is the requirement for resistor plugs with regard to electronic ignition....this is a new one for me? I have a Lucas RITA ignition, use copper plug wires and NGK BP7ES or Champion N7YC plugs.
Click to expand...


Generally digital electronic ignitions can need 5,000 Ohms suppression to protect the microprocessors from interference.

http://en.wikipedia.org/wiki/Electromag ... terference

Therefore digital ignition systems such as Boyer Micro Digital, Micro Power, Tri-Spark, Pazon Smart Fire all require suppressed plugs or caps to be fitted.

Analog/analogue systems such as Boyer Bransden Micro MkIII, Lucas Rita, etc. are not affected, so do not require suppressed caps or plugs although it is often a good idea to fit them to stop TV and radio interference which is why they were fitted in the first place.
 
What about resistor ignition wire? I used a set of Accel resistor plug wires without caps with my Boyer MK3 and non-resistor plugs. I don't recall any problems. I've since changed back to resistor caps, but I don't recall why. Probably overcome by a bout of tinkeritus.
 
JimC said:
What about resistor ignition wire? I used a set of Accel resistor plug wires without caps with my Boyer MK3 and non-resistor plugs. I don't recall any problems. I've since changed back to resistor caps, but I don't recall why. Probably overcome by a bout of tinkeritus.
Click to expand...

I'm using resistor wires on my bike now. It's just an experiment, as I needed to make up new wires and that's all I had. Some people claim that the vibration of a Norton will cause the carbon in resistance wires to eventually separate and lose conductivity, so plugs or caps are preferred.

From what I understand, SCR regulators (like the Sparx 3-phase) are prone to triggering by RF interference and can over charge your battery. My regulator is a long way from the spark plugs and I never had any problems with solid wires.
 
I've got resistor wire from Lucas Dave. They were made for bikes and have lasted a few years at least, maybe ten. I do plan to change them for solid core next tune up but they are still hanging in there.
 
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