Does anyone know for sure if the under hood harness on this engine in 1962 had a resistance wire going to the coil in it?
62 300 h.p 327 c.i.
- Thread starter Dick MacKenzie
- Start date
Thanks Paul. I know the 62 small blocks didn't have a ballast resistor. That being said I just got a new "replacement" coil and it says to use a ballast resistor. I have read that Chevrolet went to a resistor wire in the wiring harness sometime in the 60s. Don't know if that's true or if I need to find a coil that will live happily with a full twelve volts.
Look at the wire, if it's copper it isn't a resistor wire. Resitor wires are silver in color. If it's copper then just add a ballast resistor
Thanks Mike!
Under dash harness or under hood harness?
I thought the reduced voltage was on the wire from the ignition switch to the coil so you only get about 9 volts while in the run position. Doesn't the wire from the "R" terminal on the starter provide a full 12 volts while cranking?
R wire should be from ignition switch
My confusion comes from this diagram in the 1962 supplement to the 1961 shop manual. In fact the assembly manual has the same diagram. The diagram below shows a 20 ga Dark Green wire running from the "R" terminal on the starter to the (+) terminal on the coil. Also, shows a 20 ga N / R&B wired running to the firewall bulkhead connector. This wire continues in the under dash harness as an 18 ga T/W which connects into a bundle before going to the (Ign) terminal on the ignition switch. Does the "R&B" designation on the wire from the (+) terminal of the coil to the bulkhead connector possibly stand for Resistor & Ballast? 
My 63 had that resistor wire from bulkhead to coil. Hei in now and replaced that wire and terminal out of bulkhead. Those terminals are a little pain to get out of plastic housing. I saved my old wiring ant put a different terminal and wire in its place.
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Heddrik,the purpose of the resistor is to reduce the wear on the contact surface across the points.The system is set up to supply full battery voltage when starting the engine ,reduced voltage once the engine is running with the key in the run position.The "wire"is made with the necessary resistance built into it.Perhaps if you're old enough,like Phil,you'll remember being told not to play the radio with the engine in the "key on,engine off" position so as not to burn the points up.
Thank you Mr. Wizard! So it routes current differently to get lower voltage? I have rebuilt 283 and 327, just hooked the wires up and never thot about a resistor. As I said , I'm an electrical idiot. Don't understand, how 2 voltages with same wiring? Points were a PITA by the way. Lean waaay over, adjust dwell, do over in 3 months. Yuck. Thank GOD for HEI.
Do it over only if you either used cheap parts,or didn't instal them properly,like putting lubricant on the rubbing block.A well adjusted and installed set of points would last 15-20 thousand miles,or 2 sets of spark plugs.Yes HEI,or an electronic conversion kit is much better.