Bill Crowell
Member
The condenser that was supplied with my aftermarket replacement front-mount distributor was only about 75% as long as the condensers I had been using previously, so I decided to measure both kinds of condensers to see what their capacitance was. Not even close! The longer type had a capacitance of about 31 microfarads, while the shorter kind was only about 25 mfd.
I think the value of the capacitance is a fairly critical compromise, because the condenser has to have enough capacitance to efficiently absorb the spark at the points when they open, but not so much capacitance that it would take the condenser too long to discharge, because it needs to discharge quickly in order to "buck" or oppose the current flow in the coil primary, which creates a much larger voltage spike in the primary than would otherwise occur; which steps the primary's instantaneous voltage 'way up above battery voltage, which is necessary in order to induce enough voltage in the secondary for a good spark. I had been using the smaller condenser and did not like the way my 8N was running. I changed it out for the larger version, and it is running well now; however, I fixed a couple of other things at the same time, so I can't prove it was the condenser that made it run better.
<image src="http://forums.yesterdaystractors.com/photos/mvphoto4359.jpg"/>
I think the value of the capacitance is a fairly critical compromise, because the condenser has to have enough capacitance to efficiently absorb the spark at the points when they open, but not so much capacitance that it would take the condenser too long to discharge, because it needs to discharge quickly in order to "buck" or oppose the current flow in the coil primary, which creates a much larger voltage spike in the primary than would otherwise occur; which steps the primary's instantaneous voltage 'way up above battery voltage, which is necessary in order to induce enough voltage in the secondary for a good spark. I had been using the smaller condenser and did not like the way my 8N was running. I changed it out for the larger version, and it is running well now; however, I fixed a couple of other things at the same time, so I can't prove it was the condenser that made it run better.
<image src="http://forums.yesterdaystractors.com/photos/mvphoto4359.jpg"/>