Ballast wire question

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liamski
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Joined: Fri Mar 22, 2013 8:11 am
Location: Dunstable. UK

Ballast wire question

Post by liamski »

Hi
I've just fitted a Pertronix 11 ignitor and coil, was intending to hook it up to the S terminal on the rectifier, but after checking things out I suspect the ballast wire has been bypassed so I just used the existing wire and it all runs really nice.
I ran it for over 1/2 an hour took it round the block a few times got it nice and hot and it never missed a beat.
My question is would any of you guys have an idea if the resistor was still fitted how long would it normally take for it to start reducing the voltage to the coil, I'm unsure if that was long enough to run for it to drop
Thanks Liam
OZZY Stewie
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Re: Ballast wire question

Post by OZZY Stewie »

Hi Liam,
12 volts is supplied to the coil during start (cranking) and when the key springs back to run the coil gets 7-8 volts to save the points. If your resistor is bypassed you are probably already getting 12 volts.
I have Pertronic in my car and it’s great.
Stewie
1964 Ford Thunderbird Landau
And I'm living the dream!!!
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liamski
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Location: Dunstable. UK

Re: Ballast wire question

Post by liamski »

Thanks Stewie that's great,
That's what I thought, but started doubting myself and was worried the voltage would drop after a time running and leave me stranded so I thought I'd ask on here for peace of mind.
I agree it's one of the best things I've fitted, she was running well before but was just starting to get lumpy so I suspected the points were on the way out, but with the pertronix setup it's a different level so smooth and fires up really quickly.
I went for a 11 for the ignition left on protection and decided to go with a matching flamethrower coil
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sseebart
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Re: Ballast wire question

Post by sseebart »

Thunderbirds didn't come with a ballast resistor, but used a resistance wire to drop the voltage while the key is in the run position. If you're using the original wiring, you may be running at the reduced voltage. If the car is running nicely it's hard to justify jumping in with a change, but in case you have problems down the road, it's something to consider.

~Steve
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liamski
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Location: Dunstable. UK

Re: Ballast wire question

Post by liamski »

Hi
I'm sorry I probably wasn't clear enough, I'm using the original wiring as I found it's supplying 12v, I suspect it's been bypassed as after 1/2 and hour of running it was still supplying 12v with no drop indicated on the meter, but was unsure on the time taken for it to reduce the voltage after startup if the resistance wire was still fitted.
Thanks & Regards Liam
tbird
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Re: Ballast wire question

Post by tbird »

If the resister wire was still in place the voltage at the coil should drop to the lower voltage rating within the first 30-60 seconds.
Jim Mills
VTCI # 8071
VTCI 1964-66 Technical Editor
2002 Thunderbird
1965 Convertible
1962 Convertible (in progress)
1959 Ford Retractable HT
Many parts cars
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liamski
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Re: Ballast wire question

Post by liamski »

Thanks Jim
That's what I thought, but self doubt set in and I was imagining conking out whilst out on a drive, the problem I've got is the car was an estate sale and they lost all the documents so anything done to it is a bit of a mystery, also the old coil was a replacement and was completely blank,
Regards Liam
ELTBIRD
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Re: Ballast wire question

Post by ELTBIRD »

Curious why the 66 shop manual schematic on page 22-6, 22-7 does not show the pink resistance wire. It's all red/green from the ignition switch to the starter relay, then brown to the coil.
ELTBIRD
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Re: Ballast wire question

Post by ELTBIRD »

The pink(16A) resistance wire is shown in the Jim Osborn electrical assembly manual on page 82.
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