I'm referring to those ceramic ballast resistors that were used in old cars. The rectangle ones. They are .8 ohm http://www.ebay.com/itm/MSD8214-Coil-Ballast-Resistor-0-8-ohm-/380893093662?hash=item58aeff5f1e:g:rbIAAOSwLmVXDn86&vxp=mtr . I was wondering if there's an electronic equivalent resistor for this. I might have to use some on my m/c and I want to conserve as much space as possible under the tank. The m/c does NOT have points. It's a waste spark 4 cyl.
.08 ballast resistor, is there an electronic equiv
- Thread starter daves66nova
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MolaKule
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Or, you can go to the junk yard (auto dismantlers) and take the coil wire out of old point Chevies. It's easy to identify in the upper firewall loom as it's heat resistant fabric covered. All the other wires will be plastic insulation.
GM used resistance wire in lieu of a ceramic resistor block so it would take no room in your system, just wire in the loom. You want a little more hot voltage, just shorten the wire
The thing is these are not pure resistance systems in the usual sense. They are temperature variable resistance systems. They are like a light bulb. They flow full current and voltage momentarily when they are cold. But as the points (or CD box) pulls more and more pulses through them, they heat up, the resistance goes up and the voltage drops.
This is done to protect the coil during normal operation, but allow full voltage initially for cold start performance. So you need to work out how that will affect your MC ignition...
Typically the GM wire dropped it from 12.5 volts down to about 9 when warmed up ...
GM used resistance wire in lieu of a ceramic resistor block so it would take no room in your system, just wire in the loom. You want a little more hot voltage, just shorten the wire
The thing is these are not pure resistance systems in the usual sense. They are temperature variable resistance systems. They are like a light bulb. They flow full current and voltage momentarily when they are cold. But as the points (or CD box) pulls more and more pulses through them, they heat up, the resistance goes up and the voltage drops.
This is done to protect the coil during normal operation, but allow full voltage initially for cold start performance. So you need to work out how that will affect your MC ignition...
Typically the GM wire dropped it from 12.5 volts down to about 9 when warmed up ...
From the ebay listing:
"Features: Use with older points style ignitions"
You should not need a resistor except with points. The resistor is mostly to limit current to keep the coil from burning out if someone were to leave the key on with the engine not turning and the points closed. Electronic ignitions do not flow current through the coil unless the engine is turning.
"Features: Use with older points style ignitions"
You should not need a resistor except with points. The resistor is mostly to limit current to keep the coil from burning out if someone were to leave the key on with the engine not turning and the points closed. Electronic ignitions do not flow current through the coil unless the engine is turning.
Gold colored "emitter resistors" are just the thing. Small, dump heat well, and easy to mont. Just Google it to find vendors. They were used by the millions in linear power supplies.
Originally Posted By: mk378
From the ebay listing:
"Features: Use with older points style ignitions"
You should not need a resistor except with points. The resistor is mostly to limit current to keep the coil from burning out if someone were to leave the key on with the engine not turning and the points closed. Electronic ignitions do not flow current through the coil unless the engine is turning.
Wrong. The ballast resistor was bypassed during starting for a stronger spark. Many older solenoids have a "R" terminal hooked to the coil during starting.
Rod
From the ebay listing:
"Features: Use with older points style ignitions"
You should not need a resistor except with points. The resistor is mostly to limit current to keep the coil from burning out if someone were to leave the key on with the engine not turning and the points closed. Electronic ignitions do not flow current through the coil unless the engine is turning.
Wrong. The ballast resistor was bypassed during starting for a stronger spark. Many older solenoids have a "R" terminal hooked to the coil during starting.
Rod
Originally Posted By: ragtoplvr
Originally Posted By: mk378
From the ebay listing:
"Features: Use with older points style ignitions"
You should not need a resistor except with points. The resistor is mostly to limit current to keep the coil from burning out if someone were to leave the key on with the engine not turning and the points closed. Electronic ignitions do not flow current through the coil unless the engine is turning.
Wrong. The ballast resistor was bypassed during starting for a stronger spark. Many older solenoids have a "R" terminal hooked to the coil during starting.
Rod
Correct. The coil may only be a 6 volt coil and depends on the ballast resistor for normal operation. The trick with ballast resistor bypassed during cranking works because the battery voltage is reduced while the starter is cranking and it's only for a short time. Also, electronic ignitions can use ballast resistors just as points do. My MG had factory electronic ignition and used a ballast resistor.
Originally Posted By: mk378
From the ebay listing:
"Features: Use with older points style ignitions"
You should not need a resistor except with points. The resistor is mostly to limit current to keep the coil from burning out if someone were to leave the key on with the engine not turning and the points closed. Electronic ignitions do not flow current through the coil unless the engine is turning.
Wrong. The ballast resistor was bypassed during starting for a stronger spark. Many older solenoids have a "R" terminal hooked to the coil during starting.
Rod
Correct. The coil may only be a 6 volt coil and depends on the ballast resistor for normal operation. The trick with ballast resistor bypassed during cranking works because the battery voltage is reduced while the starter is cranking and it's only for a short time. Also, electronic ignitions can use ballast resistors just as points do. My MG had factory electronic ignition and used a ballast resistor.
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