Hi Danny agree , they are made of an alloy of iron , FYI the purpose is that when idling , especially with electronic( first )— there is no significant off time as solid state ignition correctly turns coil on asap after a spark and so average current can run up way high and burn out the coil at idle . Spark takes about 800 u sec , 0 .8 thousandths of a second . Why chrome box/ max wedge drag ignition had warning “ Limit idle to 30 min max” But many do not realize that electronic ignition is on all the time — if no trigger comes ( key on , engine not running ) that gets the iron ballast wire red hot , which causes it to increase a lot in ohms , protecting the coil and transistor . If you short out ballast in some misguided fairy story you WILL blow the ECU switch transistor , or melt coil insides or both . And gain zero . With points you have a minor random chance they are sitting open , ign on, but more important to understanding all this , the dwell ( on time) and the open time , are a fixed percentage of time (each ) -with points- so the average on time ,,( and thus heat in coil ) is the same % number vs rpm unlike ecu ignition which draws a little less as rpm goes up but more than points at idle . ( it is making spark more of the time at rpm than just sitting or waiting ) — why points are a less severe duty on ballast R compared to ECU — also why an ecu has more time to charge up coil at hi rpm , too . Takes about .003 sec , to full energy , (compare that to .8 msec making the spark ) you don’t have .003 on 8 cyl between sparks after maybe 4500 . At least in theory ECU control is good for maybe 1000-1500 rpm more than with points , because of that — the time the points are needlessly open after the spark happens kills you . OK in grandmas car. . And why mopar dual points helps that , about the same 1000 - 1500 rpm gain is there by more dwell time ( coil on time), equals hotter spark . second set closes early if set right , quite critical . Need dwell meter … BUT if points are randomly closed and you have left ign on , not running , iron wire gets red hot in a second , oxidizes fast etc . A Thin rusty place or end attachment burns clear . So burn outs may not all be random … ign on not running is bad news for the older ballast R . But it took 65 years to rust out .. laugh Still ballast R it is an excellent EE design imho . It tracks between the described end points too . FYI HEI controls on time before the spark to deal with this ,by looking at rpm . It lowers time on % when at low speed , that controls the current to protect itself and coil , but complicated chip inside , all analog . Why no ballast is needed —- It is pretty good too , slightly more current is allowed , probably exchanging orange box for the right 4 pin HEI yields an rpm gain . Right external coil for that is E core out of 90’s chev trucks , Polarity of pickup coil is critical . I have been looking on and off at correctly driving HEI ( or orange box ) off points , it cannot be done right with resistors despite clueless GM / Chevy web sites , as the ignition signal from reluctor is a bipolar pulse ( + and -) — resistors can’t make + into - . More to it than that , too long for here … I do like ballast R , stock setup is great , buy a good one , Standard auto parts , not T series ( low end line ) T series ( China) generally ok but this is so cheap anyway why compromise ? And try not to leave ignition on not running . If you need that , pull off coil feed wire at ballast . I promised Bob a big write up about my recent intermittent pain in ignition — in general , coming shortly . At least ballast usually goes south 100% . It is the intermittent stuff that kills you When cold , ballast is very low ohms does not reduce ignition output to any real degree . See fairy story ! It is a long EE story , as to why that seemingly obvious intuitive result is not right … It starts with coil inherent time constant L/R , — hint: note R is on the bottom , so more R …, jg On Aug 28, 2024, at 1:27 PM, dplotkin@xxxxxxxxxxxxxxxxxxx wrote: -- For archives go to http://www.forwardlook.net/300-archive/search.htm#querylang --- You received this message because you are subscribed to the Google Groups "Chrysler 300 Club International" group. To unsubscribe from this group and stop receiving emails from it, send an email to chrysler-300-club-international+unsubscribe@xxxxxxxxxxxxxxxx. To view this discussion on the web visit https://groups.google.com/d/msgid/chrysler-300-club-international/272E8E2C-CF2E-4BA9-829E-A7E0833F6149%40gradyresearch.com. |