If voltage has nothing to do with it, why is the ballast resistor only on 12 volt systems, and not 6? The 12 volt charging systems, in the 1960's, put out 26 to 39 amps (depending on application). Yet the old 6 volt charging systems put out 35 to 45 amps (depending upon application). The current draw on a 1960's mopar engine, to the coil, was 1.9 to 3.0 amps, and the ballast resistor has a resistance of 0.5 to 0.6 ohms at 70-80 F. Sort of midway of the .1 to 1 oh, of the current limiting resistors on today's cars. And I would say a built-in current limiting resistor is just another way of saying ballast resisitor. It does the same thing, only using modern technology. But that still does not answer my question. Bill Vancouver, BC ----- Original Message ----- From: "Christopher Middlebrook" <delamothe@xxxxxxxxxx> To: <mailing-list@xxxxxxxxxxxxxxxx> Sent: Saturday, February 28, 2004 12:50 PM Subject: Re: IML: 63 413 ballast > > The ballast resistor has nothing to do with voltage. It is strictly for current limiting so that you don't overload the charging system and burn up the points, or power darlington transistor in the modern case. 5-8 Amps is the nominal current depending on what type of ignition system you have. Fancy ignition systems that tout performance put out a little more current, but in all actuality, unless you are running a very high compression ratio, 6 amps is ideal. Anything more than that just puts more load on your motor from the alternator as it reacts to the additional need. > Modern electronic ignition and distributorless ignition systems have built-in current limiting resistors (.1 - 1 ohm depending on the design). This is why you seldom see ballast resistors or resistive wires any more. > > An inductive ignition system (coil) is efficient for up to 4000 RPM's. Beyond that, there isn't enough time to create an adequate field in the coil, and consequently the current limit begins to drop as RPM's increase. That's where capacitive ignition takes over. > > Chris Middlebrook > 62 Custom Southampton > > > > > --- On Sat 02/28, Bill Watson < wwatson@xxxxxxxxx > wrote: > From: Bill Watson [mailto: wwatson@xxxxxxxxx] > To: mailing-list@xxxxxxxxxxxxxxxx > Date: Sat, 28 Feb 2004 09:37:35 -0800 > Subject: Re: IML: 63 413 ballast > > <br>Actually, all North American manufacturers adopted a resistor of some sort<br>when they switched to 12 volts. Some Studebakers had a resistor wire<br>running from the ignition switch to the coil.<br><br>When the key is in the "Start" position, power is sent to the coil directly<br>from the ignition switch - a full 12 volts. Once the car is started and the<br>key put in the "On" postion, power runs through the resistor, giving about 6<br>volts at idle.. Which is why when your ballast resistor goes, the engine<br>dies when you turn the key to "On" from "Start".<br><br>During the start procedure, the resistor should show 0 volts as no power is<br>running through it as i8t is bypassed,.<br><br>Bill<br>Vancouver, BC<br><br><br><br>----- Original Message ----- <br>From: IMP7T@xxxxxxx<br>To: mailing-list@xxxxxxxxxxxxxxxx<br>Sent: Friday, February 27, 2004 11:48 AM<br>Subject: IML: 63 413 ballast<br><br><br>I assume that Chrysler is the same set up as GM. I believe that all ig > nition<br>coils are 6 volt. Your ballast resister knocks the 12 volt to six volts<br>while the car is running. During cranking you have a wire that runs from the<br>starter circuit that goes to the coil and gives the coil 12 volts during<br>cranking only. This way you get full spark during cranking. I could be<br>wrong, but donā?Tt think so. Anyone see a 6 volt car with a resister? Sooo!<br>After all this, I would say if you are questioning the resister, bypass it<br>for a test. Donā?Tt let it run to long.. If it starts and runs, you have a<br>problem in the resister. If it still does not run, something else is the<br>problem. You could also test the resister with a volt meter. 12 volts one<br>side, 6 volts the other. During crank 12 volts on both sides.<br><br>1970 Imperial<br>and a couple of street rods<br><br><br><br>----------------- http://www.imperialclub.com -----------------<br>This message was sent to you by the Imperial Mailing List. Please <br>reply to mailing-li > st@xxxxxxxxxxxxxxxx and your response will be <br>shared with everyone. Private messages (and attachments) for the<br>Administrators should be sent to webmaster@xxxxxxxxxxxxxxxx<br>To UN-SUBSCRIBE, go to http://imperialclub.com/unsubscribe.htm<br><br> > > _______________________________________________ > Join Excite! - http://www.excite.com > The most personalized portal on the Web! > >