Pertronix


http://forums.pelicanparts.com/uploa...1339416798.jpg

OK so let me test my unit like the picture above. What would I find? Obviously it works to some extent. What would the failure mode be for the symptoms I described? I could heat the unit up and do the test. My miss at 5500 would be indicated by what? My idle issues would be indicated by what?

So lets say the unit is bad. Would you trust another one? Maybe I got the one bad egg. In many years and many sets of various points I have personally never got a bad one. I will grant you somebody has, but not me.

I think in theory a contact-less pick up is a step up and I am dissapointed in what I have experienced. So I will pull my "old fart" card and stay old school, for now.

Any new Pertronix reviews?

Wondering since in today’s world it seems a lot of products change over time; materials, the way they are made etc. Also wondering since a customer has requested I install one....

No one seems to mention the fact that Pertronix relies on a solid ground connection .. and 911 engines notorious for poor grounding. Suggest an additional ground to another grounding spot from the dist body may assist .. that’s what I’m going to test on mine.

2 BMW 2002s, one “74 911S, all had pertronix installed as fast as I could get them delivered. About 150,000 trouble free miles. Do what makes you happy. I would never use points again, my lawnmower uses pointless ignition. I hear the Mclaren P1 uses points.......
If you look at the previous posts from the negative posters, you will see a trend.

I used Pertronix but have moved onto a 123 Distributor.

Mycar, How's 123 Ignition distributor compared to Petronix in your car? Was there a noticeable improvement? I'm contemplating on replacing my stock distributor with Petronix to 123 Ignition on my 70S

I’ll weigh in here from a ‘sensors’ perspective. Magnetic sensors are generally used to detect when things are open or closed or close to an object. They are good at this job but none of these jobs need to tell you *precisely* when the event happened. Who cares exactly when the door opened?

In a rotating system where a magnet passes a sensor, a variable signal is produced proportional to the distance between the magnet and the sensor. As the system spins the signal will be a sine wave of sorts, peaks occurring as the sensor is close to the magnet. . The sensor will have some kind of threshold circuit that defines the voltage level at which the event occurred - the trigger point.

The voltage level is not only dependent on the distance BUT ALSO on the strength of the magnet. In many of these points replacement systems there are six magnets set into a plastic collar. Unless there is some special selection process, it is unlikely that the magnets are the same ‘strength’, hence the signal produced will vary per magnet. This coupled with a less than precise way of setting the magnets in the collar compounds the problem and results in discrepancies between timing per cylinder.

Most magnetic speed sensors use a single magnet for good reason.

I've been reading this thread and I disagree. Hall effect sensors work great. The type of hall effect sensor used in pertronix turns on and off in a square wave pattern, not a sine wave. Very precise and defined on and off periods. A reluctor and coil sensor operates (basically a small alternator) with a sine wave. Magnet strength doesn't have to be equal either with pertronix, just magnet spacing. The distance from the magnets to the sensor is critical as too wide will result in misfires. Pertronix 1 and 2 both work great for triggering CDIs. The current and voltage stress on the Pertronix is very low in that application just as it is for points. If there is cylinder to cylinder variation it is most likely due to improperly spaced magnets. Poor quality control at the factory. I have a pertronix 1 for a Ford V8 and the variation cylinder to cylinder is precise but that particular pertronix module is very common so they probably had to get it right. Fred

Interesting video comparing points, Petronix , and 123 Ignition.

https://youtu.be/F1PFb46gKlc

Fred, you haven’t understood my points 2 and 3 below.

1) The spacing is critical which is a quality issue. You agree with me on this.

2) Yes Hall sensors work great but they don’t usually have SIX magnets. Each magnet that passes the sensor will produce a slightly different response. Usually in these sensors, the single magnet is built into the sensor.

3) Although the output of the sensor is a square wave, the basic Hall effect before the electronics will be an analog wave so there is a level threshold circuit and point at which it triggers will depend on field strength.

Yes, It's because the output is an analogue square wave that the threshold voltage isn't critical. The rise and falls of voltage are almost instantaneous so the threshold voltage will be at the correct time every time plus or minus maybe a few µS which won't be measurable. The magnet field strength just has to be strong enough so it triggers the hall effect sensor which will be at the same rotational position providing the spacing between the module and the magnet wheel is within the recommend spacing (usually 30 thou). Someone running a 20 year old pertronix will have magnets that have lost some of their oomph yet they still will trigger at exactly the same position. Fred

While tuning my 72 I got it pretty well sorted but still experienced some backfiring. Inspecting the old points they measured 10mm spacing instead of 16MM. Once adjusted the backfiring went away. New points are on order, for $5 and $5 dollar shipping.

While describing this to a Master Porsche Mechanic (highly qualified) friend of mine, he said "install a Pertronix and new coil and be done with it, $200".

I have one in my 2002 BMW, and it works great. That's what I'm gonna do.

Well. ‘almost instantaneous’ is still a slope + problems with setting the magnets IS totally measurable. In some cases as much as 5 degrees variance per cylinder.

I have a Pertronix and it's been working well after a very challenging installation (I didn't find the proper CDI wiring diagram until expending much energy in the wrong direction). It's been working well ever since, but like many others, the durability of the components seems questionable to me.

I've thought about switching to the Crane optical setup, but I've read that dirt can mess with is and at least lately, I haven't found a place to buy it (Pelican as stopped selling them).


I often think about going with a 123 distributor, so I'd love to hear more from people who have made that jump.

123 Solved a lot of problems in my '73 Alfa. Wish I had known about it earlier. Highly approve.

Does anyone know if using the stock CD coil is OK with the Pertronix? the instructions say "minimum of 1.5 ohms for the coil" and the stock Porsche coil measures 0.7-0.8 ohms.

I've a 2.7 with stock CDI / coil
with Webers with Pertronix and it's performed great.

Great. I was sketching up wiring diagrams to make sure I wire it up correctly
Top sketch is with Pertronix. Lower sketch is baseline stock.

http://forums.pelicanparts.com/uploa...1591827423.jpg

http://forums.pelicanparts.com/uploa...1591827423.jpg

I used Pertronix on a tr6 I restored and it was great, but i ve not heard the same endorsements for porsches. I m curious too if a more current opinion is available