Ballast resistor

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steve b
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Ballast resistor

Post by steve b »

I've got a Mallory distributer for my rv8 and been supplied with a coil and ballast resistor, question is - my Capri already has a ballast resistor in the loom, do I just wire the new resistor in or do I need to remove the thick resistor wire in the loom first?
Would having both resistors affect decrease the voltage to much??

Steve



DaveEFI
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Re: Ballast resistor

Post by DaveEFI »

Do you have details of the resistance value of the loom wire? Or measure it with a DVM? See if it is about the same as the Mallory one. If you can't, I'd replace it with the supplied one. You could run a new plain wire down the loom and keep the resistor one in case needed at a later time.
Dave
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steve b
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Re: Ballast resistor

Post by steve b »

Thanks for the reply 👍
I have found out that the resistor wire in my wiring gives 9v at the coil, I'm hoping to use that instead of the ballast resistor supplied to me.
Only Problem is that I can not find out whether or not 9v to the Mallory 12v coil is ok.
Would wiring in the new resistor along with the resistor wire drop the voltage too much??
It's been nearly 20 years since I partially stripped the car so trying to remember what wire went where is really hurting my rapidly aging brain😕

Steve

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Re: Ballast resistor

Post by DaveEFI »

What voltage you get depends on the load on the resistor. If you change the load, that voltage will change. I'd guess the Mallory resistor is there to limit peak current. Rather than as a cold start device, as on a points system. But can't see it would do any harm to try using your existing one. If it causes problems, change to the supplied one.
Dave
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MegaSquirt2 V3
EDIS8
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