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bear351c

Points ignition to electronic. Removal of ballast resistor.

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Hey sparkies, been a while since I've done a swap to electronic dizzy, if i remember right, the Falcons without the ceramic ballast resistor, had a Pink 'resistor wire' from the ignition to the coil. This needs to be bypassed to get the full 12 volts at the coil, right.??  The big thick pink one on the bottom of the picture, the other is the brown/red.

IMAG1634

 

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Hey sparkies, been a while since I've done a swap to electronic dizzy, if i remember right, the Falcons without the ceramic ballast resistor, had a Pink 'resistor wire' from the ignition to the coil. This needs to be bypassed to get the full 12 volts at the coil, right.??  The big thick pink one on the bottom of the picture, the other is the brown/red.
39697967941_8b4abd241a_b.jpg  

And could answer include what to do for a 250 too please?


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interested also.. pretty sure one is 12V when cranking, then drops to the resistor wire from watching a Peter Anderson Video (has heaps now i'd never find it)
 

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Alrighty then.  Cut all the tape off the loom, and traced back the Ballast resistor wire to the firewall, where it joins up to the Ignition wire. Red/grn wire 

IMAG1646

 

IMAG1645

Replaced the wire with a 10 Amp copper jobbie, now just need to insert another wire to use for the driving lights.

And re-tape the whole lot back up, nice and neat. 

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2 hours ago, bear351c said:

Alrighty then.  Cut all the tape off the loom, and traced back the Ballast resistor wire to the firewall, where it joins up to the Ignition wire. Red/grn wire 

39697967941_8b4abd241a_b.jpg

IMAG1646

 

 

Replaced the wire with a 10 Amp copper jobbie, now just need to insert another wire to use for the driving lights.

And re-tape the whole lot back up, nice and neat. 

so is that the fatter wire in the top photo? that's easy enough then, i thought it went all the way to the ignition switch 

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Quick question guys, never got around to replacing this wire when i first put the xe electronic dizzy in a decade ago. Could this be causing my tacho not to work? Or barking up the wrong tree?

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1 hour ago, Slow250XC said:

Quick question guys, never got around to replacing this wire when i first put the xe electronic dizzy in a decade ago. Could this be causing my tacho not to work? Or barking up the wrong tree?

i think it wouldn't affect the tacho, as that runs off the negative coil post

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2 hours ago, deankdx said:

so is that the fatter wire in the top photo? that's easy enough then, i thought it went all the way to the ignition switch 

Yep, the one coiled up, I thought  they went back to under the ignition barrel, but, obviously not in this case. Even the Mustangs in the 'States have a connection to the red/grn wire.  It's a bit fatter than a standard gauge wire, and has a rubbery texture, normal wire can stay straight if you point it at something, this won't.  Guess I could've used it to trigger a relay.....?

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3 minutes ago, deankdx said:

@Panko look here for falcon one

still confused. 

So can i run without it or do i need to replace it with something? 

learning here guys 

 

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Just now, Panko said:

still confused. 

So can i run without it or do i need to replace it with something? 

learning here guys 

 

on the falcon, and F100 i saw.. it's a section of "SPECIAL WIRE" chop it out, replace with normal wire..

on an escort? not sure.. but expect it's same if they don't use a ballast resistor

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1 minute ago, deankdx said:

on the falcon, and F100 i saw.. it's a section of "SPECIAL WIRE" chop it out, replace with normal wire..

on an escort? not sure.. but expect it's same if they don't use a ballast resistor

bah what a pain in the ass. 

 

ill check it out tomorrow and see what conclusions i come to. 

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(info posted here, and to the below linked thread for ref)

 

Points ignition systems, supply full battery voltage to the coil whilst cranking,

and circa 9v to the coil whilst engine is running.

 

This is to account for voltage drop during cranking, so a strong spark is provided,

(and to limit current through the points, so they last longer).

 

The resistance wire/ballast resistor, is often 1.6 - 1.8 ohms.

 

The coil positive terminal, may have two wires running to it, through one connector -

one supplies straight battery voltage ONLY when cranking,

the other supplies 9v through the resistance wire (or ballast resistor), via the run/ign circuit.

 

Electronic ignition conversions shouldn't be too fussed on voltages (12/9v), but the coil must suit the supply voltage configuration -

ie, resistor or non-resistor type.

Some conversions however, require a HEI coil - which has a very low internal resistance - circa 0.7ohms.

 

Examples:

GT40R, no ballast resistor… 14V / 1.4 ohms = 10 amps.
HEI coil, no ballast resistor… 14V / 0.7 ohms = 20 amps.

GT40, no ballast resistor… 14 / 3.4 ohms = 4.1 amps.
GT40R with 1.6 ohm ballast resistor… 14 / 3 ohms = 4.6 amps.

 

GT40 with 1.6 ohm ballast resistor... 14 / 5 ohms = 2.8 amps. (no good)

 

Part number Primary Primary Primary Turns Secondary Secondary Secondary Output KV Peak VOLTS Turns Ratio Ballast Short
  Resistance Inductance   Resistance Inductance Turns 50pf/1 Meg Current     resistance Order
  Ohms mH   K Ohms Henries   @ 100Hz Amps       number
9 220 061 100 3.1-3.4 13.8 - 15.2 345 6.8-9.2 56.7 22200 26.3 3.4 12 64.3:1   SU120
9 220 061 308 3.2-3.5 14.0-15.5 345 8.0-10.0 68.8 24500 26.3 3.3 12 71:1   GT40
9 220 061 400 1.45-1.55 6.3-6.7 240 6.8-9.2 50 22200 32 5.24 9 92.5:1 1.5 SU120R
9 220 061 430 1.25-1.35 6.3-6.7 240 8.0-10.0 66.1 24500 29.1 3.7 9 102:1 1.8 GT40R

 

image.png

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I have been running a GT40 coil with my standard Bosch points system, since I rebuilt the 302W engine 13 years ago. It runs smooth as glass most of the time but sometimes grumbles and runs rough. I could never figure out why. Is it because it has a GT40 instead of a GT40R???

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