Electronic Ignition Opinions Needed

I have drove my a on long trips several hundred miles a trip and so for never had a break down, thank the lord. After listing to all the people that have it is scary. I have been told it is easier to change out the fs then the points and adj them. I have installed and adjusted a lot of points, but never changed the fs in my car after installing it. So i can"t say which is easier. I will carry a spare and hope i never need it.
 
RobertB said:
Related question...I've added an MSD module (capacitive discharge) on each of the British cars I have owned and had very satisfying experiences.

On the MGB, I invested in a Pertronix distrubutor that never worked and was not backed by the supplier. I installed a "new" standard distributor and that helped, but nothing like the change when I added the MSD.

Has anone done this to their Model A? The MSD kits come for 4, 6, and 8 cylinders...wouldn't the 4 cylinder work on the A engine? A new coil installed with it is a given.

RBH
New to my 31 A, but old to cars of many types.
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Robert,
Yes I have an MSD on my Model A and a Petronix as the trigger for it. I wired it in such a way that if the MSD failed I can simply switch a couple connectors around and the Petronix will drive the coil directly. If the Petronix fails I can simply install some points and away I go. In the future I plan on building an A distributor with MSD's reluctor & pick-up and replace the old MSD6A with a programmable MSD6AL. This will allow me to program (and tune) a timing curve. Whiled I'd agree this is overkill for a Model A I used the MSD simply because I had 2 of them sitting on the shelf collecting dust, with no car to use them on. I will say this: It starts super fast and doesn't miss a lick.

Tom
 
AL in NY said:
Brent in 10-uh-C.....Post 14
"Now with that said, the Pertronix unit is only a triggering system, ....therefore it cannot produce a hotter spark the coil does that."

Brent in 10-uh-C.....Post 4
"Therefore the risk involved in accidentally leaving an ignition switch on to cause a module failure,.........is just not worth the effort/expense on 90% of typical Model-A applications IMHO."

Brent, I have to take issue with both of your above staements. First, when the Pertronix module is used in place of points, it will produce a hotter spark because the dwell time is much longer allowing the coil to build up more energy to produce a hotter spark when the points open. This is the purpose of dual points, they keep the points closed as long as possible. Second, the newer Pertronix modules have been modified so they don't fail if the ignition switch is left on. I know is for a fact because I tested it myself.

The Pertronix electronic points module is extremely reliable when installed correctly (as per their instructions) and they eliminate the rubbing block wear seen on standard points. Your timing doesn't change over time and the hotter spark makes cold weather starting easier.
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Again, this is where folks are not paying attention to the details. Bill Stipe's newly designed distributor cam will produce dwell times that will rival the electronic triggered system. The 2nd side of this is coil saturation will only go so far. You can only get so much voltage out of a particular coil. Again, we NEVER discussed changing coils to a "hotter coil". Only to change the triggering system.

I can tell you from experience that a Pertronix system will NOT start easily if the battery is weak.



I also think it is grossly unfair to make statements having folks believe that a Pertronix system can deliver 5 mpg more than a stock points system. That is like a 20%-25% increase in economy which I doubt could be seen even if someone had a worn-out distributor cam and a burned set of points.

I will also say that many, MANY folks have driven thousands of miles without a single misfire also using points. There is also many who can testify as to their failures. Again, the biggest reason why there was an advantage nearly a decade ago with the Pertronix was a top-quality distributor cam was unavailable and good-quality points were in short supply. This gave an advantage to the electronic triggering system however that has all changed now. If we ever do another Workshop here, this may be one of the very tests we will make on a chassis dyno. I suspect there will be some who are not happy with the results. ;)
 
MALAK said:
Robert,
Yes I have an MSD on my Model A and a Petronix as the trigger for it. I wired it in such a way that if the MSD failed I can simply switch a couple connectors around and the Petronix will drive the coil directly. If the Petronix fails I can simply install some points and away I go. In the future I plan on building an A distributor with MSD's reluctor & pick-up and replace the old MSD6A with a programmable MSD6AL. This will allow me to program (and tune) a timing curve. Whiled I'd agree this is overkill for a Model A I used the MSD simply because I had 2 of them sitting on the shelf collecting dust, with no car to use them on. I will say this: It starts super fast and doesn't miss a lick.

Tom
Click to expand...

It might be worth noting that Ford used a "Multiple Spark Discharge" set-up WAY (i.e: like 60+ years before!! :eek: ) prior to Autotronics ever "inventing" it. Think about it!! ;)
 
Keep it going guys !! Good post !!! I am staying out oft for a while as it would take me too much time to respond.

I learned in the auto servie industry problems we " real----imagined ---or alleged
thats what this post has covered for sure.

Brent let me know if you get that workshop planned i would like to attend,,,,,
 
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There is something that has bothered me for years.
Points are NOT pointed. They have a slightly spherical surface.
Some of the cheap early ones were flat.
Therefore I think they should be called "spheres".
Makes just as much sense as the renaming of most of the scientific terms several years ago.
I am now going to go for a ride on my bihertz.
 
Brent in 10-uh-C: I was unaware of the Bill Stipe distributor cam and after searching Bill's site I can not find it. As for the hotter spark, I made no mention of using a hotter coil, just replacing the stock points with the Pertronix module. The increased dwell time over stock points and cam would produce a hotter spark.
 
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Brent is correct on some failures, we installed one of the Zippers when we were in Texas. At about 3,000 miles it failed. FS replaced the module again at 3,000 miles it failed. At this time we changed modules from Pertronix and have not had another failure since 2008. This is in the sedan and gets several thousand miles a year of use. The failures came when we were actually running the car about 3,000 miles a month so it was quite evident there was some problem with the module they were getting from Pertronix, we spoke to Pertronix at the SEMA show right after the problems and they suggested the other module that we have been using. But, I do carry a spare module just in case. The change out is very quick probable faster than points once you know what you are doing.
 
Here's the scope pattern using original points and slant pole coil in my 1928. This first picture shows the coil primary pattern. The coil primary and conderser form a tuned circuit, where the electricity flows back and forth between the two until the plug gap no longer has enough voltage to fire the gap. The remaining energy still bounces back and forth until it dwindles to a very low straight line, then the points close as shown by the drop on the right side.

The second picture shows the coil secondary with all 4 plug patterns superimposed. Notice the spark isn't just one instantanious spark, but continues for as long as the coil primary can supply enough energy to power the secondary to fire the gap. At that point you will see a rise in the line above what it took to maintain the spark, but it takes more voltage to restart the spark than it took to maintain it.

Anyway the stock system works fine and trouble free for me, and is so easy to fix if something was to go wrong.

Anyone have a scope picture of the electronic trigger system?
 

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While Brent is getting re-educated in electronics, I will say that I will have a ED system in my modelA soon because I have had a Pertronics in my antique Plymouth for 16 years and 70,000 miles and no problems! Ron W
 
AL in NY said:
CarlG: How did you find that page on Bill's site? I have always used this link http://www.specialtymotorcams.com/index.html. Can't seem to find the home page for the link you suggested.
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He actually has 2 web sites. The home page for the page I listed above is:
http://www.stipemachine.com/
It's a little tricky navigating. On the menu list on the left side of the page, just point at the very bottom of the box before clicking on it. If you click directly on the name, nothing happens.

BTW, I bought one of these for myself and another for a friend. Both of us are very satisfied with the increased performance.
 
Still on the waiting list for the new/improved 'point' trigger auto advance rebuild unit, from Bubba....as backup for my 10 year old Pertronix ...long lasting unit !
 
Tom Wesenberg said:
Here's the scope pattern using original points and slant pole coil in my 1928. This first picture shows the coil primary pattern. The coil primary and conderser form a tuned circuit, where the electricity flows back and forth between the two until the plug gap no longer has enough voltage to fire the gap. The remaining energy still bounces back and forth until it dwindles to a very low straight line, then the points close as shown by the drop on the right side.

The second picture shows the coil secondary with all 4 plug patterns superimposed. Notice the spark isn't just one instantanious spark, but continues for as long as the coil primary can supply enough energy to power the secondary to fire the gap. At that point you will see a rise in the line above what it took to maintain the spark, but it takes more voltage to restart the spark than it took to maintain it.

Anyway the stock system works fine and trouble free for me, and is so easy to fix if something was to go wrong.

Anyone have a scope picture of the electronic trigger system?
Click to expand...

Tom,

I do have a collection using the scope and amperage waveforms just need to dig up on my shop laptop...once upon a time we used the scope to analyze everything and every waveform with actual current waveforms of coils etc...
 
I think they were called points orginally not because they are/were pointed, more because they are "points" of contact. It's interesting that they are being called "points" on a mostly US based forum as I've always thought that they were mainly referred to as "contact breakers" in the US, which as with most US terms is a more accurate description of what they actually are/do :)


Regards

Kevin

Reading UK
 
It is correct that the Pertronix Ignitor II is overload protected. I have one in an antique boat and accidently left the ky on for one week! NO damage to the ignition module!
 
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