Dura Spark Dizzy and Ballast Resistor ????

[60RatRod]

O.K. hit the junkyard again (hopefully third times a charm) picked up a Duar Spark Dizzy Motorcraft P/N 12127 and Ballast Resistor with pat # 254186 got em both from about a 74 thru 76 F100. The ballast resistor looks like an ol School resister and the dizzy doesn'nt have the adapter. Are these components a good match. Also Dura Spark 1 ? Numbers Dummy maybee you can help with the P/N's
Thanks Dan

[Franklin2]

Do you have a module? That will plug into the distributor wiring.

[60RatRod]

Yep, got that. Along with the 12V coil stamped for external resistor, all off the same truck.

[60RatRod]

Found the dizzy P/N covered in grease
DOZF
12131A
18

[Franklin2]

If you got it all off the same truck, they probably will all hook up. The module should have blue plastic where the wires go in. Since you got it off an older vehicle, if it's the original module, it may have black plastic where the wires go in. The black plastic was the early style module, but as long as it works, your ok.

[60RatRod]

I geuss I'll wire things up and see what happens.

[60RatRod]

O.K. done wiring things up and she fired up first try, runs pretty damn good. Question now is what do I regap the plugs at? I am at .35 with autolite plugs on a 390 motor and I've heard everything from .44 to .50 any ideas?

[Franklin2]

Like everything else, sparkplug gaps are a compromise. The wider the gap, the more spark energy you get. But the wider the gap, the less life the plugs will have. Usually .45 is a good compromise for long life. If you want to go wider, you can, but your wires need to be in really good shape, and put replacing the plugs on a reasonable preventive maintenance schedule.