What are the +/- of a Pertronix Ignitor II vs I?

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Hi all. I tried to read all the posts on the Pertronix ignitors and still don't know whether to buy a I or II. Any help? Also, can I get the correct part numbers for a 351C 2V? I know I don't want the III after reading the posts. Thanks! Kevin.
 
Didn't the 2 fix the issue that if you leave the key on but not running you'd burn the pertronix up?
 
Last I knew the Key On safety was the main improvement from 1 to 2. Strange that Pertronix doesn't say that in their product descriptions (maybe the lawyers told them to admit nothing regarding burned out P1 units).

P1:

Product Info​

  • Delivers twice the voltage to the spark plugs, increasing horsepower, fuel economy, and spark plug life.
  • 2:1 improvement over "points" in current fall time for increased coil output.
  • Rotating cobalt magnets trigger a Hall Effect integrated circuit . ...no points to burn, ...no moving parts to wear out.
  • Epoxy molding makes our module impervious to dirt, oil, grease and moisture.
  • Stable timing ...no need for any adjustments.
P2:

Product Info​

  • Adaptive dwell maintains peak energy throughout the entire RPM range, reducing misfires while improving engine performance.
  • Develops on average 4 times more available energy between 3000 and 5000 RPM, and 2 times more available plug voltage.
  • Compensates for inherent electronic delay by adjusting the spark timing throughout the entire RPM range.
  • Synchronized peak current and spark timing reduces heat build-up.
  • Senses startup and develops more energy for quicker, easier starting.
P3:

Product Info​

  • Multiple sparks thru the entire RPM range.
  • Integrated digital REV limiter with LED feedback for precise RPM setting.
  • Memory safe function stores settings eliminating unintended changes to Rev limit.
  • Adaptive dwell maintains peak energy throughout the entire RPM range, reducing misfires while improving engine performance.
  • Peak current level is reached just prior to spark for maximum energy without the heat build-up, increasing coil performance and module reliability.
 
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Thanks for the replies everyone. I'm going to go with the PII as this car doe snot have a factory tach.

Kevin.
you could pull the 12V from a relay. Pertronix list one, but perhaps any 12 V relay would work. I went the hard way and bypassed the old pink resister wire with a 12 gauge (red) wire directly to the coil. My advice, do it the simplest way.
 
Thanks Geoff!
You could add a Rocketman's tach conversion. Very good and very easy to do....... and while you're in there, a good set of LED bulbs from Bill at HiPoParts.com. Oh how I love spending other people's money!! I have more suggestions if you ask.
 
Use the red w/yellow hash marks wire that powers the throttle position / anti dieseling solenoid. It'll give you full battery voltage in crank and run modes.
Someone who had our 73 Mach 1 before me rerouted the wiring harness and the Circuit 640 Red Yellow hash wire for the TPS that is no longer present. Rather than dig around in the rerouted harness I just spliced into the Windshield Wiper Circuit 63 red wire for switched battery voltage on our Pertronix installation. I had previously tapped into Circuit 63 to power the aftermarket Holley electric choke (requires 12 volts, not the alternator stator 6v AC circuit), so the wiring to splice into was conveniently located.

For another installation with a stock 2100 carb I used the oem electric choke circuit (alternator stator Circuit 4, White Black stripe wire) to trigger a relay that provides the 12 volt switched battery voltage for the Pertronix distributor module. That required minimal disruption to the oem wiring & harness, and still got me the result I was after.
 
First post... I acquired a 71 Mach 1 that I thought was well sorted except the tach didn't work. Pulled the cluster to find a rat-nest, wiring nightmare - all aftermarket, solid colored wires, nothing like Ford's wiring schematic.
Will spare you details, but it also has a Pertronix III and coil... the previous owner said the tach worked for him then failed after gauge lights started failing.

Question: Can the Pertronix III cause problems with the tach operation - even if the resister is removed. (Also non-Ford wiring in the engine compartment.)

Clear as mud?
 
First post... I acquired a 71 Mach 1 that I thought was well sorted except the tach didn't work. Pulled the cluster to find a rat-nest, wiring nightmare - all aftermarket, solid colored wires, nothing like Ford's wiring schematic.
Will spare you details, but it also has a Pertronix III and coil... the previous owner said the tach worked for him then failed after gauge lights started failing.

Question: Can the Pertronix III cause problems with the tach operation - even if the resister is removed. (Also non-Ford wiring in the engine compartment.)

Clear as mud?

Welcome to the forum!

Short answer - yes. The only wire that should be on the coil (+) is the feed from the tach. Move the Pertronix power wire to the Red w/Yellow hash mark wire, which is a single rubber bullet behind the driver's side valve cover.
 
Thanks for the reply, Hemikiller! Restoring my GT5 Pantera eons ago was a lot less complicated.

Car wiring makes my head hurt!

When I disconnected and pulled the cluster/tach I found, shown in IMG 2372, a connector plugged into the tach - but with only a solid purple wire spliced to the connector on one side. The other side was just terminated.
Essentially the tach had only one wire attached.
IMG_2372.jpeg
And, using a test light, I was able to determine that the purple wire was wired to accessory. I don't know how the tach ever worked with only one wire, especially that one. Printed on the purple wire is "Elec Fan Relay".

In IMG 2373 photo I discovered two wires resting loosely with the rest of that mess that were tagged but terminated - just taped off.
IMG_2373.jpeg
The red "12 volt power" wire is just that - only on when acc. is on.
The purple "Tach from coil" wire does seem to be from the coil, as it flickered with using test light on it with the engine running. (that's about the extent of my electrical expertise). It also has "Tachometer" printed on the wire.

Unfortunately, I couldn't locate any Red w/Yellow hash marked wires in the engine compartment as they're apparently replaced by an aftermarket harness and loomed. But you can see in IMG 2369 that the coil has TWO wires on each terminal. I traced the one l labeled "Tach" as what seemingly feeds the tach wire mentioned above and is marked "Tachometer". The other (red) goes to the distributor (unmarked) as does a black wire on the negative pole. The purple coming off of the negative coil post goes goes into the loom toward the dash - but is also marked "Tachometer".
IMG_2369.jpeg
Here's the kicker! When I jumped what appears to be the working purple "Tach from coil" wire from under the dash, and a acc power source (like the red "12 volt power" wire to the tach), the engine immediately shuts down.

I did confirm that a tach does work if jumped directly between the positive coil post and positive battery post.

So, is this thing possible wired incorrectly at the coil or somewhere?

WTF, chuck? (head throbbing)
 
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Welcome GT5, from Oklahoma. It looks like you have a recurring nightmare wiring harness. You might consider contacting "Midlife" on this forum. He restores wiring harnesses and may be able to source a complete and correct harness for you. Chuck
 
Welcome GT5, from Oklahoma. It looks like you have a recurring nightmare wiring harness. You might consider contacting "Midlife" on this forum. He restores wiring harnesses and may be able to source a complete and correct harness for you. Chuck
Thanks for the advise - I'll certainly look into Midlife for his expertise. And thanks to anyone else who has .02 for me.
 
Welcome from SW Ontario, GT5.
Wow that looks like a real mess, like someone had a bunch of lovely colored wires and decided to "have a go" at redoing the harness.
I thought mine was bad enough whereby someone installed an aftermarket radio, but instead of just spicing into the harness, they cut off all the connectors, then added wires just twisted together and taped.
As for the PIII, I had a really bad experience with one of those whereby the plastic so-called "bearing" between the plates (Ford version) wore out with a few months. Short version; Pertronix replaced it with a PII and matching coil at no charge. Not had a problem since. Mind you, I did have to learn how to rebuild and recurve my stock Autolite dist. for ultimate timing.
 
Thanks for commiserating, Stanglover,

If this car were for sale in its current state, knowing what I know now, I would not plunk $ down for it. But, it was a gracious gift from someone close who over the years lost interest.

I have/had? grand plans to clean it up to the '71 I had in high school. Lots of new and used parts on the way, body and paint lined up, upgraded the 9" with a Tru-Lok - and then I find this mess behind the dash, including the cowl rusted through - and I just want to scream.

But the motor is strong... I have that going for me.IMG_1764.jpeg
 
I just installed a Petronix II on my 73 Mach along with a new Edelbrock intake and Holley carb with an electric choke. I pulled my 12V for the
choke from the wiper motor to power the choke and also send 12V to the flamethrower coil. I have the 12V wire, red wire from the PII and tach
wire going to coil positive and the black wire from the PII to coil negative. The factory tach now reads way low. I contacted Petronix and they suggested I try a resisitor in the tach wire. I've attached the instructions they sent me. We'll see if that fixes the tach
 

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