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  • 1965 - 1973 Classic Mustangs -General/Talk-
  • Classic Mustang Specific Tech

Resistive Coil Wire With New Coil

  • Thread starter Thread starter tx65coupe
  • Start date Start date Apr 2, 2009

tx65coupe

Active Member
Nov 29, 1999
1,551
1
37
Apr 2, 2009
#1
  • Apr 2, 2009
  • #1
I have a Pertronix Flame Thrower II coil on my 65. Can I hook it up to the factory coil wire? It supplies resistance when running but not when cranking.
 
F

ForceFed70

That's why they call it "dope"
Founding Member
Dec 6, 1999
4,818
1
69
BC Canada
Apr 2, 2009
#2
  • Apr 2, 2009
  • #2
I would bypass the resistor wire, but it should be fine without bypassing.
 

Mil1ion

New Member
Feb 26, 2009
48
0
0
Apr 2, 2009
#3
  • Apr 2, 2009
  • #3
From this:


12. If converting from a point type ignition, remove any resistance wire, or
ballast resistor that may have been previously used.
If a resistance wire is present: replace the wire with a 12-gauge copper
stranded wire. Most resistance wires begin at the engine compartment
side of the
fuse block.

~~~~~~~~~~~~~~~~~~

It appears the pertronix system runs on 12 volts not 7-9 volts like the OEM system.

So a by-pass of the resistance wire from the ignition switch is needed
 

tx65coupe

Active Member
Nov 29, 1999
1,551
1
37
Apr 4, 2009
#4
  • Apr 4, 2009
  • #4
Thanks for the input. I am going to bypass the ballast resistor wire. I just wanted to see what others thought about this.
 
C

c24sc

New Member
Jan 1, 2008
114
0
0
Apr 4, 2009
#5
  • Apr 4, 2009
  • #5
tx65coupe said:
Thanks for the input. I am going to bypass the ballast resistor wire. I just wanted to see what others thought about this.
Click to expand...

Yup. Bypass it. It drops the volts to stock coil down to ~6-7Volts so that it wouldn't burn the factory points out. But will have problems with pertronix coil with the low voltage. Go straight from the key switch, and bypass the stock wire.

Nate
 

tx65coupe

Active Member
Nov 29, 1999
1,551
1
37
Apr 5, 2009
#6
  • Apr 5, 2009
  • #6
I installed a new larger 12 gauge wire for the coil. I left the stock wire in place and ran the new one along with it in the harness.
 

Tim65GT

Active Member
Feb 24, 2004
1,149
2
39
West Texas
Apr 5, 2009
#7
  • Apr 5, 2009
  • #7
You said you have the Pertonix coil, but do you have the pertronix module in the distributor, or are you running points?

The purpose of the resistor wire is to save the points from burning up.
 

tx65coupe

Active Member
Nov 29, 1999
1,551
1
37
Apr 5, 2009
#8
  • Apr 5, 2009
  • #8
I have a Pertronix Billet distributor with the ignitor II module. So, I don't have points. I'm glad you brought that up though. That way anyone that reads this thread will know about the issue with points.
 
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