points and electronic ignition
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points and electronic ignition



Richard, I concur with your orientation.  When points are properly set up AND there is the correct lube on the rubbing block (key issue!), they'll last pretty good.  Points will also start when an electronic system will not as ANY battery voltage that will produce a spark might fire the motor off whereas any electronic system has to have a particular voltage for the triggers to even work.
 
And example -- Several years ago, a friend in our Mopar Club took his restored Daytona wing car to Mopar Nats for the Concours Judging.  Part of that judging at that time was that the car had to start and drive up on some "oil change" ramps so they could judge the underbody areas.  My friend had not made sure the battery was charged up before he left, but it would start the car.
 
As the judging progressed, the doors were open and he'd had to start it to get it out of the trailer.  When it came time for the underbody judging activities, he tried to start it.  It cranked over very slowly, almost like it was not going to turn another revolution--but then it fired and started.  If it'd been an electronic system, it would not have started due to that voltage requirement issue I mentioned.
 
One other thing that was mentioned in the better conversion kits from the early 1970s was "ignition retard" compared to points.  Seems that the electronic systems would retard the timing 1 degree per 1000rpms.  I never saw anything in the Chrysler literature about it, but Hays and a few others had it in theirs.
 
The main issue with electronic ignition is a properly timed spark that happens the same way all of the time and "no points to change".  With the coming emissions issues, electronic ignition's consistency in spark timing (cylinder to cylinder) was important with the added benefit of no maintenance.  The sparks are no hotter than what a points system would produce as the Chrysler systems used the same coils (the electronic ignition coils replaced the point system coils in the Chrysler part number system a while back, I believe).
 
The factory OEM Chrysler systems require about 8 volts minimum to run the box whereas the MSD boxes require about 6 volts on a 12 volt system.  The "Orange Box" that Chrysler supplies with their Mopar Performance Electronic Ignition conversion kits requires closer to 10 volts minimum, so for a non-race application, the normal box works fine.
 
I have observed that many in the old car hobby per se do seem to prefer the Pertronix conversion.  I believe there are now two levels of control modules for them too.  Yet many in the Mopar hobby per se seem to prefer the Mopar Performance kit as it comes with all of the wiring and such to make it work.  The normal kit has a vacuum advance distributor (new) and the Chrysler recommended performance advance curve.
 
I put one of those kits on my '67 Chrysler Newport 383 4bbl.  It went in like it was made for it.  I found a good place to mount the control box inside the left front fender extension and made an extension harness that runs along the left inner fender with the regular harness.  I still use the original voltage regulator too (the one Mopar Perf recommends keeps the voltage too high and as it states in the Race Manual, the higher voltage will affect the durability of every electrical component in the car, including light bulbs).  I set the timing to about 12.5 degrees BTDC and that works fine (it has 906 heads on it so the compression ratio's closer to 9.0 CR).
 
The advantage of the Mopar Perf system is that it's all new stuff.  Adding a conversion kit to an existing distributor that has some bushing/shaft wear might not be the best thing around in some respects.  Other than the extra wire coming out of the distributor housing, everything looks completely stock too.  Even for some of the Mopar hobby purists, this conversion is accepted as an OK deal with no points deductions in many judged shows.
 
Another friend swore by the Jacobs system and had it one his cars.  But when another friend tried the same system on his car, it became clear that it took much more re-engineering to make it work and that our first friend had a sizable long distance bill with their tech line.  It went away and the previous Mopar Perf system was reinstalled.
 
The advantage of the MSD boxes is their multi-strike capabilities up to about 4000rpm or so.  Seems that they ought to be great with some wider gap plugs with their multiple firings for 10 degree (or so) of crank rotation.  Sounds good in theory, at least.
 
The OTHER main issue with points (other than shaft/bushing wear) is wear on the lobes of the breaker cam the points' rubbing block rides on itself.  The high spots can wear down with use, but you might not notice it unless you put a dial indicator and check each one as it rotates (best done with the distributor chucked in a vice).  The point gap AND dwell readings must be in specs for things to work correctly and rubbing block wear and breaker cam wear will keep that from happening.
 
In one respect, if the points you have in there now are doing OK, then keep an eye on them and check the dwell with a quality dwell/tach meter from time to time.  They will not wear out overnight, unless the rubbing block is unlubed.  A quality set of points might be hard to find today (plus having the little vial of grease packaged with them!) and it might be a little tricky to set the gap, but if they're set up correctly and everything else is in good shape, they should last pretty well (remember that even the old 12,000 miles between tune ups can now be several years worth of driving in a collector car that sees occasional use). 
 
On another note, even if you put a "hot" coil in the ignition system, it's not going to put a 50KV spark out every time, it'll put out just enough to fire the plug and that's all.  The stock systems would do something like 32KV, as I recall and that was plenty.  Adding some modern plugs (gapped perfectly to factory specs) that take less juice to spark plus a set of plug wires (the lower resistance magnetic suppression wires) will make things easier on the system too.
 
Just some thoughts,
W Bell
 
 
 
 


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