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Usually standard coils store between 10,000 to 18,000 volts (other performance coils goes up to 48000 volts).
The bad news: more voltage imply less point life. Due it, usually pointless pickups (like pertronics) replace points on engines with performance coils. Also many performance coils need a ballast resistor set on series with the coil.
We also can use a electronic amplifier (computer ignition) between points and coil, making four advantages over replacing points with a pointless pickup:
1) A more powerfull voltage (build by the amplifier), make a more powerfull spark (by example, a MSD 5 sent 375 volts to the coil, points send only 12 volts to the coil). Pointless pickups dont add additional voltage to spark, only assure a good and reliable calibration (we can combinate a pointless pickup like the pertronics with a amplifier like the MSD 5 or 6).
Of course, if the problem is a wobbling distributor shaft, the ideal solution is a pointless pickup.
2) On some amplifiers, at low speeds the spark are "divided" on three sparks (milisecs spared), maximizing the probablilty of ignition (less misfires), it is usefull at low speeds (less of 3000 rpm); on high speeds (more of 3000 rpm) a single powerfull spark is best (usually that amplifiers hand it, cutting the spark division after 3000 rpm).
3) Due the points are used only for "timing" the amplifier (then no big current run across points) it don´t erode (the points has a very longer usefull life).
4) If the amplifier unit broke, you need only to reroute the cables, returning to the original points setup (is a bit more work if you need to replace the electronic pickup with points in middle of the highway - I speak by personal experience).
Two types of amplifiers are available on market:
a) The inductive discharge ignition, it work on stock vehicles with no performance upgrades (with original camshafts and carburetors, engines running under 6000 rpm). Examples: MSD 5, Crane 700. It is ideal for daily conmuters, but not for pure sangs.
b) The capacitive discharge ignition. Used on upgraded street machines and street rods (engines running between 5000 and 15000 rpm), it will ensure complete combustion and high intensity spark. Examples: MSD 6A, Crane 7000.
Some additional info can be found on the Internet searching for articles writed by Christopher (Chris) Jacobs (the guy is a type of guru on ignition topics for race teams on US).
Happy volving,
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Joaquin (yogui the bear) / Rojo 121 / Lima, Peru
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