Duraspark Conv ???

[NVbronco2]

I have read most all of the info on this but....

My coil says it needs a "ballast resistor" to work? My local Ford friend says the same thing. How is this wired in? What do I need to buy? There is a good writeup here on the conversion but it didn't say anything about this.

Next: where can I find a new plug for the Auto trans back up switch? Mine is FOBAR and I need to replace the plug for new wires.

Thanks guy's

 

[kimcrwbr1]

In the tech library is a schematic for the duraspark with the ballast resistor. Your better off just using the stock TFI coil the square one it dont need a resistor and works best with the stock plugs. To make a ballast resistor work and have the start circuit retard the timing correct you will need to add a diode in the start circuit so you can start it with battery voltage to the coil for quick starting but it will run the coil through the resistor in the run position so you dont burn up the coil. The stock TFI coil produces about 30% more voltage than any resistor type coil you would be better of just getting a coil that runs off battery voltage you get a much better spark and just use stock motorcraft or autolite single platinum plugs. Anything else is just overkill oh yea dont get bit with the tfi coil it will wake you up real quick.

 

[Big Jim M]

The answeris...

I have read most all of the info on this but....

My coil says it needs a "ballast resistor" to work? My local Ford friend says the same thing. How is this wired in? What do I need to buy? There is a good writeup here on the conversion but it didn't say anything about this.

Next: where can I find a new plug for the Auto trans back up switch? Mine is FOBAR and I need to replace the plug for new wires.

Thanks guy's

What the resistor does is reduce the voltage going INTO the coil down to 6/8 volts. MODERN coils run at 12/14 volts and don't need that resistor.
Which ever you do use they all OUTPUT about the zact same voltage. ANY new coil will run our little engines.
Big Jim

 

[NVbronco2]

OK But.....
Why did the article on the "conversion" call for the round coil that I bought? Now that it is all wired up (old cut out) and the new in, what do I need? I haven't even started it yet (no carb) and now I need to change it?

I guess the article needs to be updated!!!! Like, what do you do with the auto trans backup/neutral light switch, the vacume line connections and anything else that a new Bronco2 owner might need to know.

Boy howdy is the wife getting P.O. about the $$$

 

[kimcrwbr1]

You can try just wiring the coil + thru a ballast resistor and see if it works. The rangers dont have the same ignition as the older duraspark systems with two start circuits on the key. What you can do is use the start wire at the starter solenoid and run it back to the coil for more power at the coil for quick starting but you need to put a diode in line so the voltage dont back feed to the start solenoid in the run position. So from the start solenoid run a wire back to the module white wire from there through the diode to the coil + that will retard the timing and boost the coil voltage for quick starts.

 

[kimcrwbr1]

Find the hot key on and run that to the red on the module and then thru the resistor to the pos on the coil.

 

[Big Jim M]

What!

You can try just wiring the coil + thru a ballast resistor and see if it works. The rangers dont have the same ignition as the older duraspark systems with two start circuits on the key. What you can do is use the start wire at the starter solenoid and run it back to the coil for more power at the coil for quick starting but you need to put a diode in line so the voltage dont back feed to the start solenoid in the run position. So from the start solenoid run a wire back to the module white wire from there through the diode to the coil + that will retard the timing and boost the coil voltage for quick starts.

That DIODE is a terrible idea! When it goes south and you are 30 miles backwoods...what do you do then?
Please don't advise this.. If you have it done I strongly suggest you take that diode out and find another place to get your start voltage.
Big JIm

 

[kimcrwbr1]

That DIODE is a terrible idea! When it goes south and you are 30 miles backwoods...what do you do then?
Please don't advise this.. If you have it done I strongly suggest you take that diode out and find another place to get your start voltage.
Big JIm

It would be better to not even use a resistor type coil. I doubt you have ever did the conversion on a ranger BII you would know the diode is the only way to get starting voltage to the coil. On older fords they had two start circuits from the ignition switch the ranger has only one. If you know a better way that would be more productive than just saying find another way.

 

[kimcrwbr1]

If you still have the computer harness there is a diode that goes to the computer from the start circuit that will work just fine the engine will still start all it does is boost it to batt voltage for quick starts.

 

[85_Ranger4x4]

OK But.....
Why did the article on the "conversion" call for the round coil that I bought? Now that it is all wired up (old cut out) and the new in, what do I need? I haven't even started it yet (no carb) and now I need to change it?

I guess the article needs to be updated!!!! Like, what do you do with the auto trans backup/neutral light switch, the vacume line connections and anything else that a new Bronco2 owner might need to know.

Boy howdy is the wife getting P.O. about the $$$

They are replicating the exact way it was set up originally on the Pinto/Mustang II. The other way is taking advantange of more modern parts that are now available.

This is how I did it with the factory coil and it served my 2.8 great for about 3 years. Rather than mess with the resister and all that I just found a wire that went to the coil that was hot in the "run" position and tapped into it (and not with a POS scotch lock either) The coil was apparently happy before with whatever voodo happened upstream before the swap and seems to still be happy. My 302 plugged right in to where I unplugged the 2.8 and ran perfect for the first time tonight.