To Pertronix or not?

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bluecs

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I'm thinking of using Pertronix on my 74 e9. However, in my readings I have come across comments alluding to getting stranded.
Share your experience with Pertronix or other solutions to points.
Thanks
 
My Crane XR 700 looks like hell but has been reliable for more than 15 years. I worry about being stranded so I carry a set of points just in case. And there's always AAA.
 
When I bought my car it had running problems which were the result of bad points. I changed to a Pertronix and that issue was resolved. I don't have a lot of miles on it, so can't speak directly to longevity/getting stranded but I believe a good backup plan is to carry a good set of points to swap out if the Pertronix fails. Pretty quick to do. I don't believe that any company stays in business for long if they continue to produce a product with a high failure rate, though it's true that heat is the enemy of electronics it's hard to say what the eventual life span will be. Certainly longer than traditional points which require regular maintenance & replacement.
 
mulberryworks said:
When I bought my car it had running problems which were the result of bad points. I changed to a Pertronix and that issue was resolved. I don't have a lot of miles on it, so can't speak directly to longevity/getting stranded but I believe a good backup plan is to carry a good set of points to swap out if the Pertronix fails. Pretty quick to do. I don't believe that any company stays in business for long if they continue to produce a product with a high failure rate, though it's true that heat is the enemy of electronics it's hard to say what the eventual life span will be. Certainly longer than traditional points which require regular maintenance & replacement.
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I have been running a Pertronix unit for over 20 years. On the track, around town, multi-hundred mile trips. Never blinked once!
 
I ran pertronix without issue for a few years. Had a backup but never needed it. Moved to 123 distributer and never looked back. The various forums have examples of people occasionally stranded by the pertronix i guess they occasionally go bad. I also think some of that is user install error.
 
What happened when I ran a Pertronix, despite running the required 3 ohm resistance, was it would get hot and shut the car off randomly. Some days I'd drive 2 hours and it would be fine, other times 10 minutes. Since it was so random we went back to points & condenser and the car ran great for weeks. Went with a 123 Distributor in 2016 for our cross country drive with no stalls or stutters.

Ran a Pertronix in my 2002Tii with no problems util the original distributor failed after 43 years. Used an Ireland Engineering mechanical advance distributor for a year then put in a 123 Distributor.
 
I've used a Crane optical trigger and ignition box for years in the 911, first the XR700 and now the HI6. They've worked well and the HI6 CD unit is a noticeable upgrade over the conventional ignition.

A few years ago I put a pertronix in the coupe along with the budget MSD unit. Both have worked well for me.

Hagerty Pertronix article by Rob Siegel
 
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One thing that may bear mention and I'll start with a question: why use a Pertronix (lotsa reasons).

But I think to get an advantage other than possibly a "hotter" spark, you should know that the brass cam gear and brass distributor gear are in good condition and there isn't so much slop between them that the hotter spark advantage is lost in timing changes of a couple degrees.

So get out the timing light and run the engine at idle, while looking at the ball on the flywheel, or notch in the front pulley. If it varies by, say, 1/8 inch, you've got a wear issue that a Pertronix can't fix, since it uses the same shaft on the diz as do the points.

Others should chime in on this...
 
Honolulu said:
One thing that may bear mention and I'll start with a question: why use a Pertronix (lotsa reasons).

But I think to get an advantage other than possibly a "hotter" spark, you should know that the brass cam gear and brass distributor gear are in good condition and there isn't so much slop between them that the hotter spark advantage is lost in timing changes of a couple degrees.

So get out the timing light and run the engine at idle, while looking at the ball on the flywheel, or notch in the front pulley. If it varies by, say, 1/8 inch, you've got a wear issue that a Pertronix can't fix, since it uses the same shaft on the diz as do the points.

Others should chime in on this...
Click to expand...

Indeed. My Pertronix install got my engine running, but I was unable to properly time it because the timing was so erratic that I literally couldn't see the ball, even after painting it white. Since you can apparently only get some of the parts listed for a distributor rebuild, I found a rebuilt one on an auction site near you.

My car went from not running in my garage on Maui, to running and licensed with new tires and off to the docks for shipment to Austin where I now live. After a brief trip for lunch at an adjoining town during which I had a number of misfires and a couple of carb coughs, I put it in the garage and started planning the rust repair which where things are now.

So though I've owned the car over 5 years now, I've driven only a few tens of miles, more for the Flintstone floor and bad motor mounts than the running issues, but at least the Pertronix got it running well enough to make the boat to the mainland.

If I had a known good engine to diagnose or improve, I'd probably strongly consider the 123 distributor. As it was, the Pertronix was a reasonable cost way to sidestep the flakey points issue, which as it turned out was only part of my problem, but enough to get me where I was going.

Here's a pre Pertronix attempt to start.
 
I'll add that when a friend got a factory long block 2002 motor from BMW and we installed and fired it up, the timing light showed the little ball on the flywheel was steady as a rock. Try get that with a 40-year old car. IIRC he may even have been using his old diz, suggesting that the drive on the camshaft was the weak link.
 
I have been running Pertronix on two different cars for over ten years. I had a problem with one that was installed by the previous owner. It was good for about 4 years and the sensor burned out. That is when I learned about why they fail. Everything must be set up properly to get long life out of them. The coil must have the proper resistance for the type of Pertronix used (I think they have 3 different versions). The voltage to the coil must also be correct for the type of Pertronix being used. This information should come with the type of Pertronix you purchase. Just read the instructions and do exactly what they ask for. You can call Pertronix if you don't understand. They are very helpful, at least they were with me.

After I knew more about how to set them up, I was surprised it lasted as long as it did. Everything was out of balance on the car (a 69 Fairlane Cobra) in which the Pertronix failed. The sensor totally fried. The one I installed on my Coupe has been trouble free and the one I replaced on my Fairlane Cobra has also been working for around 15 years trouble free.

I carry a set of points and condenser in each car as insurance. I have not needed them yet. I really like not having to adjust or replace the points periodically. And the ignition timing doesn't change over time due to wear on the points.
 
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for some non technical reasons i will try not to use pertronix or 123distributor

the optical solutions might be a good idea, but i have no experience
i used points for a while, and i got tired
so i decided to use a period correct transistorized ignition, this worked and still works fantastic, excellent response in all the rpm range including 6000+ rpms, points are still there, but they do not suffer, as the main current goes through the transistorized box, points only trigger the ignition times to the transistor
it is a bosch kit dated 1975

here is the oszilloscope analysis,...perfect shape of primary and secondary curves, the raster view is extremely good, condenser is not used and transistor circuit gives much better response with sharper attenuation ...



here it is the original thread,...

help, transistorized ignition, original BOSCH

hi, i have just bought an original transistorized ignition system from boschconsists of a electronic box and a coilthis system is intended to keep the points, but having the benefit of avoiding the major intensity of the current to pass through them, permits a better performanceof the spark...
www.e9coupe.com www.e9coupe.com
 
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I agree with the use of transistorized ignition system. Many years ago I had a 1973 FJ55 Landcruiser that liked to eat points. I installed an aftermarket transistor ignition system and drove it for 10 years without having to change the points again. I did periodically measure the point gap to check for mechanical wear of the point cam rider. I don't recall having to make an adjustment.
 
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