ballast resistor for ponts distributor question

DanEC · #1 (**permalink**) 05-06-2011, 06:22 PM

I'm planning to run an old dual point 427 distributor in my FE motor in my ERA (I believe it's a 63 model from memory). I thought if I could find anyone who still had a ballast resistor listing in their books, I would be fixed up. NAPA had one for a 63 427 and ordered it but when the parts guy and I opened it up we were both surprised to find a resistor wire harness (1.3 ohm) rather than the resistor coil/isolator I'm most familar with for Mopars and GM cars.

I'm not that familar with older Ford cars - does this resistor harness sound right or should I keep looking?

thanks

Dan

mr bruce · #2 (**permalink**) 05-06-2011, 06:30 PM

Ballast Resistors - SummitRacing.com

Rick Parker · #3 (**permalink**) 05-06-2011, 08:46 PM

OEM Ford applications had a specific length of Resistance rated wire leading from the switched source (Key) to the coil. Initially 12 volts passed and within a couple of minutes when the current began it caused the wire to become warm and increase the resistance rating, causing the voltage drop which would save the points from burning. High performance coils such as Mallorys Voltmaster used a ballast resistor and regular wire to handle the extra current demand.

DanEC · #4 (**permalink**) 05-07-2011, 04:04 AM

Right now I'm planning on using an OEM replacement coil, etc so I guess the Ford resistor wiring harness may work. Since Cobras were not OEM Ford built cars in most respects, I wonder what Shelby installed in the street cars when he put 427 and 428s in them - Ford OEM resister wire harness or a resistor coil?

Rick Parker · #5 (**permalink**) 05-07-2011, 06:16 AM

I believe the technology was the same for many British cars too. The BMC Minis that I had in the past did not have Ballast resistor either, they used resistance wire. Find some examples of OEM wiring diagrams from the 60's in some "Chilton or Motors Manual books " at a library and you will see the (+) coil wire willl be noted as resistance wire. Cheapest way to achieve the desired results in an OEM appplication, especially in a damp environment (England). Fewer connectors to corode over time.

mreid · #6 (**permalink**) 05-07-2011, 02:56 PM

Fords used the resistor wire that you have. Also, make sure you install the bypass wire from the "I" terminal on the starter solenoid to the distributor side of the resistor wire. This bypasses the resistor during cranking to give you the best current for starting your beast.

DanEC · #7 (**permalink**) 05-07-2011, 02:58 PM

Great - thanks for the help all. I'm going to print this thread out for reference.

Dan