Question for GTK?

[Don Coatney]

On the main site supporting this forum in the parts listing section I see a seporate parts listing for 12 volt ignition points as pasted below.

Points for 12 volt Conversion CS725A Magnition AL8890AS. This being listed as a NAPA part number.

My question being does NAPA actually list a different part number for 12 volt points? It is my understanding that all point fired ignition systems actually run on 6 volts due to an internal or external voltage reducing resistor.

[Guest P15-D24]

hence the 12 volt designation. I would be really surprised it the was actually physically different from the standard part listed for a 6 volt system. I don't see any reason why the 6 volt points would have or need a voltage reducer. They are basically just an on/off switch.

[ptwothree]

Hi Don...Looks to me like the same points (CS725A) are used in both 6 and 12 volt settings. Seems I remember most 12 volt ignitions run at around 9.5-10volts. This extends the life of the points.

The move to ditch 6volts was the result of lots of things including lack of ignition stability as compression ratios rose during the 50's.

I experimented with running straight 12v. to the coil as a drag racing "speed trick". Worked for 4-5 runs then had coil and or points problems.

So it would seem, points do well up to around 10 volts or so, same for 12v coils. And 6 volt coils do better at 10v then 12 v coils do at 6v. But not by much.

[LuckyDevil]

So I don't need to replace my points with the points listed on the main page under 12 volt conversion?

[steveplym]

So I don't need to replace my points with the points listed on the main page under 12 volt conversion?

Nope all you need is a ballast resistor with a coil that isn't internally resisted.