New purchase of an old part

[deathsled]

I am done with Pertronix. Going to use a dual points distributor now and picked up this Motorcraft dual points distributor today in what appears to be excellent shape. Looks like the code on it says 3D8 in addition to the C5OF12127 which I am told is an early 70s replacement for the HiPo. Only wondering if I should swap out the gear on it given my current engine in the Hertz is a mid to late 80s 302 with a roller cam in it. But it also has roller rockers. Not sure if a roller cam and roller rockers can coexist but definitely has the roller rockers. The gear on a distributor has to match the gear on the camshaft from what I have researched and recently learned. The distributors from that era were mostly cast iron gears and the gear on an 80s Mustang 302 is steel? Therefore change out to a melonized gear?

[hertzz350]

Just wondering, why did you go back to points?  I have never ran Pertronix in my shelby.

[pbf777]

    A "mid-80's 302", . . . . . well '85 was the first year for "hydraulic-roller camshafts" in the "5.0" ("302"), so be sure that yours is such.  Then if it "is" the O.E.M. steel-billet hydraulic-roller camshaft, then yes, you will need to utilized the appropriate "steel" distributor driven gear vs. the older "cast iron" gear as was of previous flat-tappet usage. 

    Scott.

[deathsled]

Just wondering, why did you go back to points?  I have never ran Pertronix in my shelby.

I had my Hertz spontaneously quit on me on two separate occasions, one time being on the Interstate at speed. I would have to pull over and once it cooled down it would start again. I replaced the small module in the Pertronix billet distributor the first time it quit and the problem went away. For a while. A few years later it did it again and once more I replaced the module inside the distributor and it solved the problem for a while. There is a third wire that gets spliced to the ignition switch but after reading about many others having Pertronix problems I am going to revert to older technology. Yes, points need more maintenance but it isn't difficult maintenance. And they are easy to replace. Condensers can go bad but they are plentiful at swap meets and likely eBay too.  Plus it looks more stock in the engine bay even though the script should read FoMoCo but those FoMoCo factory installed distributors are hard to find and tend to be rather expensive. I can live with a Motorcraft one.

[deathsled]

The offending part.

[deathsled]

A "mid-80's 302", . . . . . well '85 was the first year for "hydraulic-roller camshafts" in the "5.0" ("302"), so be sure that yours is such.  Then if it "is" the O.E.M. steel-billet hydraulic-roller camshaft, then yes, you will need to utilized the appropriate "steel" distributor driven gear vs. the older "cast iron" gear as was of previous flat-tappet usage. 

    Scott.

Fairly sure it is an 86 engine that was built for drag racing. But using a composite gear is compatible with everything so I am leaning toward that option than risking premature wear of one of the gears.  I will have to change out the Flamethrower coil too so as not to burn up the distributor. Something that runs 9 volts rather than 12.

[shelbydoug]

Converting the original ford ignition to the MSD can be tricky.

The Ford is actually a 6 volt system. The wire that supplies power to the system is connected to the ignition switch which is 12 volts. But it is connected to a pink resistance wire that reduces that voltage. It will be 9 volts cranking but is actually a 6 volt supply running.

The MSD will actually run if connected to that resistance wire but it will cause it to fail within almost a predictable period of time.

IF you want to run the MSD, then you need to run a new 12v wire from the ignition switch.

Without actually seeing your set up, by the failure description of yours, I would expect to find that it runs off the original pink resistance wire.


I prefer the points system. I don't put on enough mileage to make it a burden to run it. Frankly, I think that the Ford dual points gives equal voltage to the plugs as any aftermarket system does.


You are going to need to source a "yellow top" Ford coil to use with your new Ford distributor.

[deathsled]

Converting the original ford ignition to the MSD can be tricky.

The Ford is actually a 6 volt system. The wire that supplies power to the system is connected to the ignition switch which is 12 volts. But it is connected to a pink resistance wire that reduces that voltage. It will be 9 volts cranking but is actually a 6 volt supply running.

The MSD will actually run if connected to that resistance wire but it will cause it to fail within almost a predictable period of time.

IF you want to run the MSD, then you need to run a new 12v wire from the ignition switch.

Without actually seeing your set up, by the failure description of yours, I would expect to find that it runs off the original pink resistance wire.


I prefer the points system. I don't put on enough mileage to make it a burden to run it. Frankly, I think that the Ford dual points gives equal voltage to the plugs as any aftermarket system does.


You are going to need to source a "yellow top" Ford coil to use with your new Ford distributor.

Points for the win. They worked. They won races as part of a system back in the 60s. You and Uncle Tony agree.

[pbf777]

Fairly sure it is an 86 engine that was built for drag racing.

    This would generally mean we have no idea what the makeup might be; and the original year of production is irrelevant.  So what camshaft is in that engine now? 

But using a composite gear is compatible with everything so I am leaning toward that option than risking premature wear of one of the gears.

    The advent of the "composite" gears was/is due to the flood of import camshaft cores and that no one knows what'll work with what!  And I've been aware of many a scenario where they "didn't" work 

     And believe it or not, in the earlier renditions of the hydraulic-roller from Ford they initially utilized a "bronze" gear; but that didn't work to well in the long-haul, as anybody whom had used them with their mechanical roller cam could have told them! 

    Scott.

[pbf777]

I prefer the points system. I don't put on enough mileage to make it a burden to run it. Frankly, I think that the Ford dual points gives equal voltage to the plugs as any aftermarket system does.

Points for the win. They worked. They won races as part of a system back in the 60s. You and Uncle Tony agree.

    That all sounds good, but the simply stated the old '60's "20,000 volt" points system, that as compared to a more modern "40,000 volt" aftermarket electronic system, will provide "less" in overall performance and peak power. . . . . . period!   

    Scott.

[deathsled]

Fairly sure it is an 86 engine that was built for drag racing.

    This would generally mean we have no idea what the makeup might be; and the original year of production is irrelevant.  So what camshaft is in that engine now? 

But using a composite gear is compatible with everything so I am leaning toward that option than risking premature wear of one of the gears.

    The advent of the "composite" gears was/is due to the flood of import camshaft cores and that no one knows what'll work with what!  And I've been aware of many a scenario where they "didn't" work 

     And believe it or not, in the earlier renditions of the hydraulic-roller from Ford they initially utilized a "bronze" gear; but that didn't work to well in the long-haul, as anybody whom had used them with their mechanical roller cam could have told them! 

    Scott.

I've interrogated my father about the camshaft but he's turning 98 in April and doesn't remember anymore. When I pull the Pertronix I can gauge what sort of gear it has and also check for wear and if all seems good, I will go with the same gear which I suspect is steel. I am willing to sacrifice some performance in exchange for more predictability on the road. I'm not doing holeshots with the car and not breaking down while on the move is preferable to top end power.

[98SVT - was 06GT]

Swap the gear from your current dist. You know that works with the cam.
There is a specific way to wire the Pertronix so it doesn't fail. Check their website for the diagrams.
Pertronix DO NOT like solid core plug wires.
Coils are 6V (yeah I know some are marked 12V). They get 12V to start from the solenoid. The pink wire in the Mustang harness is a resistor wire that runs the coil on 6V. A lot of Pertronix problems come from using that wire.
A high voltage coil will work on points too - get an epoxy one rather than oil filled. The current condenser market has a lot of bad product floating around - carry a couple spares.
I've got one of the early flat top HP Mallory dual points and a set of NOS points and condenser. I've been reluctant to get rid of it because as you said "They worked. They won races as part of a system back in the 60s."

[pbf777]

There is a specific way to wire the Pertronix so it doesn't fail. Check their website for the diagrams.

    +1     And it's not complicated!   

    We have sold, installed, utilized Pertronix for decades and have found it to be quite reliable, when wired properly.  But also, I do like to couple it to an MSD box; . . . . . always looking for more ya'know!   

    Pertronix is susceptible to damage from voltages in excess of 16V, so ensure that it doesn't experience external charging (battery charger or jumping) voltages much over 15v and also check the voltage regulator function and the alternator's out-put under "full-fielding"   

    Cause you really shouldn't be having this problem.     

    Scott.

[S7MS427]

There is a specific way to wire the Pertronix so it doesn't fail.

Yup, and if you do  it correctly, it is pretty easy.

+1     And it's not complicated!   

    Pertronix is susceptible to damage from voltages in excess of 16V, so ensure that it doesn't experience external charging (battery charger or jumping) voltages much over 15v and also check the voltage regulator function and the alternator's out-put under "full-fielding"   

    Cause you really shouldn't be having this problem.     

    Scott.

+1. I've used PerTronix on both of my cars for many years. Mostly because I don't like setting points, especially dual points. Not that it is difficult, just annoying. I alway take the 12vdc off the ignition circuit BEFORE the tach and resister wire by plugging in a pre-made single wire with moulded in male and female bullet connectors at either end and then splicing the red wire for the PerTronix into that. That way, there is no damage to the wiring harness and it is easily removable. The Hertz car uses the Ignitor I while I have an Ignitor III in the GT500. And I carry a spare breaker plate in the glove box just in case the thing goes sideways.