The Stovebolt Site Forums The Shop Area The Electrical Bay Ballast Resistor

Where can I get a Ballast Resistor for the ignition? I'm converting to 12 volts and have everything but the resistor. Another question, where is the best place to mount it? 1953 5 window, 3100.

charlie

Aftermarketers like Jim Carter,LMC,Classic Chevy,etc. sell them.
I've seen them mounted on the upper firewall, but I think any convenient spot for you would work.

you can get one at NAPA, ask for one for 56 up .... also make sure the 12V coil you get is for the external resistor

Bill

I already have the coil, how can I tell if its for the external resistor?

new ones usually say on them, at least if they're internally resisted they say 'not for use with external resistor' - if it's an original from before the 60's it'll be for use with the resistor

Bill

So lets say my new one is not for use with an extrnal resistor, do I still need the resistor?

no - the resistor is bypassed when the starter is engaged by the way it's wired up, the 6V wiring doesn't have the bypass function so you should have a 12V starter with the bypass provision

the resistor lowers the voltage so the coil and points aren't fried - the internally resisted coil keeps the voltage at the right level all the time - if it's internally resisted and you add the external resistor, it won't hurt anything but it might be hard starting [load of starter reducing current to coil] .... if it's not internally resisted everything will still work, but points won't last long and the coil will eventually fail, maybe soon

Bill

Locate your resistor where it will get the least road splash,they get hot you know.

If you look this problem up in past posts you will see where I was looking for some of the same information. We were working on a friends '36 streetrod truck. Problem....after several years of no problems, after engine was good and hot and at idle, engine would die. Coil was very hot. After cool down engine would restart. Coil was matched with aftermarket Mallory HEI type distributor. Placed ballast resistor in system with new Mallory coil. Did not fix problem. Replaced electronics in distributor and again, it didn't fix it. At wits end, I gave him a GM performance or racing coil and the problem went away. Coil never gets over lukewarm. Why...ya got me, it just works.