Thanks John, very informative…as usual! Bob J From: chrysler-300-club-international@xxxxxxxxxxxxxxxx <chrysler-300-club-international@xxxxxxxxxxxxxxxx> On Behalf Of John Grady I think there is a little misunderstanding in some of these posts? if you listen carefully , Carl correctly explains clearly you can get the 12 v module operating voltage directly to the module via the red wire placed on the hot end of the ballast — but note the ballast will still remain in series with the coil to protect it ! Leave that alone ! Thus there are two feeds to deal with - not one . . So apparently the red wire is powering the electronic circuitry , nothing to do with ballast or coil current part of circuit . It is obviously the correct way . Second , the coil can only take a certain current that is set by the summation of the coil ohms and ballast R ohms . Too much current will overheat it . You need that total resistance to get to the design value of around 5-7 amps , says ~ 2 ohms or so . More current will overheat the coil at idle , when dwell time between sparks is long . Special low ohm coils need special ignitions . Don’t mix this up . All the hype about high performance or high volt coils are advertising junk . More coil volts = less current = less heat ( just like a welder ). Coil watts for the physical size of it are constant , Volts times Amps . Just like a power transformer — On Secondary side too . A watt second is a joule , or millijoule , the energy you have . Better to have the correct lowest voltage needed ( 25-40kV ) and higher current for a hot spark !!! Can’t have more of one without cutting the other , no free lunch . Lower primary coil ohms or no ballast means burned points or overstressed modules that get hot . ( HEI gm actually controls the current — how they get away with no ballast ) . The factory engineering guys who designed all this knew all of these variables far better than any aftermarket guy trying to sell you stuff , and it is very highly optimized stock . over 100 years of optimizing .... The big issue in high performance is the dwell at high RPM — not these other things . Points are open too long , between sparks, the spark weakens . There is not enough time to fill up the coil , before the next spark, which takes a known time L/R . ( note more L , (bigger coil ) takes longer , R larger fills faster (!) . = Ballast helps!!! Electronic igniting greatly increases dwell at high RPM as it closes the circuit again right after a spark , so a better fill up of coil , good for another 1000 rpm . Single points are starting to hurt at 4500 rpm . That exact same concern is why we have our dual points , second set closes immediately after first opens , that increases dwell . But very very fussy to set perfectly . You have to use a dwell meter . Most of the issues and whining are because they are just not set right ( true!!!) and they always move as you tighten the screw . old fashioned analog Dwell meter tells you that . Related to Carl’s mention of grounding , the stock dual points ( when unmolested by an “expert “ ) have a bare grounding flex jumper from the moving plate to the fixed plate . If missing , make one ... I did not see it in Carl’s picture . And Thermal contact grease ( like used in power transistor mounting ) would help the pertronix live by keeping it cooler . I share the feeling it seems to have very little heat sinking for the current being switched ... And yes on an electronic transistor switch you lose a volt , —-spark energy goes as E sq R , 13 sq is 169 , (~ 170 ) 12 sq is 144 . —hmmm . Why you see 16 v systems on drag racers . Maybe points are not so bad if you want to win Last , I looked at a lot of coils etc a few years back after getting irritated by wild claims and hype of Jacobs ignition ,Jacobs coils , MSD , Accell etc the best “ stock” coil parameter set is ( not surprisingly , designed by GM in 1990’s) the potted E core external one used in Chevy trucks with HEI in 90’s . ( not one in the cap) Ought to work well with our ballast R but non stock look . Cover the bow tie with a magic marker ! John Sent from my iPhone not by choice
I watched the video. My impression is that those of us using Pertronix with success are the rule and not the exception, otherwise this item would not remain on the market. However especially after watching the video I would urge those using these to carry a spare module or better a set of points, condenser and the screws with you. Just in case. I watched the video. It did a wonderful job of convincing me to stay with my properly adjusted dual points. Seems to me that Pertronix instructions ought to be clear on whether the ballast resistor (which exists to limit primary current and not voltage) should remain in the circuit. On the one hand is the warning that the ballast must not be in the circuit and on the other advice that there is very little heat sinking on this lima bean sized module switching raw un-ballasted primary current. Chrysler advises that electronic voltage regulation be used with its over the counter electronic ignition. I would imagine that a Pertronix unit would struggle on a generator equipped car at a stop light, foot on brake, regulator cutout open and radio or lights on, but maybe not. I'll stick with my previous advice. If you run Pertronix and stray far from home, keep a set of stock ignition components with you, including the screws and tools. That is what many of my Corvette friends do. My Corvette uses its stock GM K66 transistor ignition, a different animal but one capable of causing similar anxiety. -----Original Message----- Thanks Carl, I’ll check out the video. I’m running an original coil, and I’ve had no issues. It seems as though bypassing the ballast would depend on the coil used, I don’t think you’d want to do it with a stock coil, I know I’m leaving well enough alone. Bob J From: chrysler-300-club-international@xxxxxxxxxxxxxxxx <chrysler-300-club-international@xxxxxxxxxxxxxxxx> On Behalf Of Carl Bob et. al. If you have a stock style coil that is not internally resisted, running a full 12V (14+V when running) will mean increased current runnig through the coil which means more heat which means a drastically shortened coil life, irrespective of points or electronic switching. At least that is my understanding. An EE like John Grady can explain more precisely. If you run an aftermarket coil with the Pertronix Ignitor, such as a Pertronix coil, which is internally resisted, then you don’t want the ballast resistor in the circuit. And yes, the Pertronix Ignitor module will function a lot longer if it is supplied by the 12V side of the ballast. Every few months or so we revisit the Pertronix issues on this listserver, and we have been doing so for at least the last 22 years. In that timeframe Pertronix has developed newer and better units (Ignitor 2 nd 3) and upgraded the base Ignitor 1. The majority of the problems with these are installation related, and always have been. But they can and do fail for a number of reasons with time and use. I did a video back in August about the Pertronix Ignitor I after 10 years or so of use in my J. Just my thoughts but might be helpful. It is found on our Club Website in the Tech Dept. or here: Pertronix Ignitor - YouTube Carl Bilter From: Bob Jasinski Ray et al, Thanks for posting this. So, I’ve had a Pertronix installed in my G since 2011, and have had zero problems and enjoy faster starting and lower idle speeds than with points. You stated “The first was failure to supply a constant 12 volts to the Pertronix unit, instead of the reduced voltage supplied (after startup) through the ballast resistors commonly used to reduce erosion of the original points”. I just pulled out the Pertronix installation instructions received with the unit and it clearly states in all caps “NOTE: A RESISTOR WIRE OR BALLAST MAY OR MAY NOT BE INCLUDED IN THE ORIGINAL EQUIPMENT. THEY ARE NOT TO BE CHANGED IN ANY WAY WITH THE INSTALLATION OF AN IGNITER SYSTEM”. The wiring diagram (attached) does show the Ignitor (Pertronix) unit connected to the 12 volt side of the ballast resistor, running on 12 volts, however, you also state “ I also filled in the backside of the factory ballast resistor to provide constant 12V to the distributor as required by Pertronix”. Please explain why you did that? Is there a benefit to supplying full voltage (12V) to the coil all the time? My understanding is that the coil is only to receive 12 V when cranking, not running. Has Pertronix changed the instructions to now state 12V to the coil full time? Bob J From: chrysler-300-club-international@xxxxxxxxxxxxxxxx <chrysler-300-club-international@xxxxxxxxxxxxxxxx> On Behalf Of Ray Melton Hello All - Regarding John Grady's and Dan Plotkin's experience - Like many of you, I was aware of the somewhat spotty reputation of some of the Pertronix ignition conversions, and I researched the many comments on multiple automotive boards. I spoke directly with a representative at Pertronix about my specific applications (1957 Chrysler 392 Hemi and 1967 Porsche 912). He readily acknowledged those complaints and said that the Company had made several incremental changes to improve reliability, and then (not defensively) explained what they felt was the source of most of the failures. The first was failure to supply a constant 12 volts to the Pertronix unit, instead of the reduced voltage supplied (after startup) through the ballast resistors commonly used to reduce erosion of the original points. Whatever is in the Pertronix Hall-effect magnetic sensor does NOT survive long with that reduced voltage. The other factor was that the Pertronix kit was adversely affected by the back-EMF Radio Frequency Interference inherent in early wire-core ignition cables like the ubiquitous Packard 440, and therefore RFI- suppressed resistor wires were required. He acknowledged that the instructions included with each kit did NOT adequately emphasize those requirements for 12v supply and resistor ignition wires (including coil), and agreed that he would transmit those recommendations to his upper management for clarification in future instruction sheets. He said that the Pertronix units would sometimes fail within six to 24 months if the correct voltage and ignition wires were not supplied; it was literally running on borrowed time from the outset. The rep also pointed out that some older coils may have experienced degradation (often through heat and vibration) that caused their resistance to exceed the specification range required by the Pertronix sensor. That is especially true with their newer Ignitor II kits, which require a coil with very low resistance, approximately 0.6 ohms, compared to the typical 3 ohms with most older coils. He also recommended the epoxy-filled versions of their coils for improved tolerance to heat and vibration. I suspect that if many of the previous complaints about failures were fully researched, we would find that the (admittedly poorly disclosed) operational parameters of the Pertronix kit were not met, either initially or during subsequent operation. Call Pertronix directly at (909) 493-5467 if you have questions; I found their representative to be quite knowledgeable, patient and genuinely interested in providing the best product for your application. (NO affiliation) https://pertronixbrands.com/ Ray Melton (Yes, I HATED adjusting the dual points on my '57, even with a dwell meter - crawling into the mouth of the "Whale", bracing myself on the carburetor for 40 minutes of trial-and-error inside the distributor, standing tippy-toes on a stepstool over the fender, YUK! ************************************************************************************************** On 12/1/2021 10:55 AM, Dan Plotkin wrote:
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