Thread: Another stupid question from Hoof, distributor wiring?

Tweet

I got a "one wire" coil over rotor distributor for my 400 Ford (don't say M!). There are only two terminals, one is marked tach (obviously the drive for an electronic tach), and the other +. I am assuming that the 12 volt power to the distributor would get wired on the positive terminal, but it is a very small connection. I would have expected a stud for a hot wire, not a little spade terminal, could this be right? Sorry, no pics, but the tach terminal and the + power terminal are the same size?

The directions with the unit are less than useless. At what amp level should I fuse the distributor? A simple disconnect in that power line would work to fire and kill the engine correct?

Thanks,
CHAZ

I have installed several of these. just use a slide on female connector. I don't fuse my ign hot wire. jim. hope this helps.

Thanks, I just can't believe that little connector carries enough juice!
CHAZ

How have they worked out for you? I got mine pretty cheap so I am skeptical of its quality.

I wouldn't use a fuse but I would use a fusible link.

Originally Posted by hoof

Thanks, I just can't believe that little connector carries enough juice!
CHAZ

The "juice" is in the coil. The juice/current that + wire carries is very small compared to the juice/current that the coil puts out.

Just a heads-up to those of you who plan to swap to a one-wire HEI. If your vehicle was originally equipped with a points-type ignition system (generally before about 1973), you must run a fresh line to the + terminal on the distributor from the ignition switch. Cars equipped with points had a ballast resistor or resistor wire in series with the hot line to the coil to reduce voltage after a few minutes of run time. 12v was supplied on initial start-up, then was gradually reduced to 6v to prevent burning the points. So, if you use the same line that was used with points, you will experience poor results with the HEI.

the coil works thru induction. the trigger turns the coil ground on and off, so the primary windings magnetic force collapsing and turning back on, induces a charge in the secondary windings, and there are more secondary windings than primary's, that's how you get 40,000 volts, or 20,000 volts, whatever your working with BUT, the coil can draw 40 amps intermittantly, this is why you don't fuse.

Originally Posted by Matt167

the coil works thru induction. the trigger turns the coil ground on and off, so the primary windings magnetic force collapsing and turning back on, induces a charge in the secondary windings, and there are more secondary windings than primary's, that's how you get 40,000 volts, or 20,000 volts, whatever your working with BUT, the coil can draw 40 amps intermittantly, this is why you don't fuse.

True, but the discharge path of the secondary is through the large coil wire to the distributor cap's center tap through the rotor bug to each individual plug wire. There will never be 40 KV on the positive wire to the coil.