MSD distibutor giving me a hard time

[ntsqd]

The hype mostly is due to the module, which is easy to use with a D-S II distributor.

ETA: Just found this in doing some preliminary research for such an article: https://www.carbdford.com/tech/HEI/hei.htm That'll get most anyone started if not all the way there.

 

[DirtDonk]

I don’t know why, but for the last couple of months, one of the search suggestions that comes up whenever I click on the Internet on my phone, is the “Dyna-Mod GM 4-pin module“ from DUI performance distributors.
I guess we talk about it enough that it is trying to get me to buy one.

We should be saving a lot of the old Dura Spark module cases. Especially with the fins on them.

 

[ntsqd]

My perception may be skewed because of the circumstances at the time. The last D-S II module that I ran I felt was better than the MSD-6 that it replaced, but it wasn't anything exceptional. Competent and reliable, but not exceptional. When I put the HEI module on the Valiant it replaced a Mopar electronic ignition module (actually several different modules as they were NOT competent or reliable) and the HEI module was clearly a superior module in every way. Engine started easier, had more power, and just generally ran smoother and better.

So that leaves me with the idea that the HEI module is better than the D-S II module. I know that some purists will never put such a module on their Ford vehicle(s). I get that, not what I would do, but I can understand it.

What I don't like about the HEI module is that some or all of the connections are not sealed. Those modules that do have sealed connection only have them for power and coil connections. The induction trigger connections are still simple spade terminals. Those are the connections that are most susceptible to corrosion causing problems. To offset this on the Valiant I fully covered each terminal with adhesive lined heat-shrink and filled the connector with dielectric grease before making the connection.

The very first HEI module conversion that I did on anything was on MISF's Scout II. I put a D-S II reluctor and pick-up coil in the IH engine's Prestolite distributor. It had previously been trying to use an ancient Stinger conversion kit. We hollowed out the Stinger module's cast housing and hid the HEI module inside of it. That ran exceptionally well. MISF then decided that he wanted to run an MSD-6OR. I honestly can't see any improvement, but he likes it.

 

[DirtDonk]

So the GM module with the sealed terminals, is only on half of them? For some reason, I thought there was a module version that had all terminals using the sealed type connector.

 

[ntsqd]

The 4 pin & 7pin HEI Modules are all unsealed. The 8 pin HEI module is sealed for power, tach, & coil, but not for the pick-up assembly.

There is a module shown on the Performance Distributors modules page that they refer to as "Vortec" that I am not familiar with. It could be sealed for the pick-up wires and it may not be. None of the pictures that I've seen of it so far have been much help in sorting that out.

 

[EPB72]

The 4 pin & 7pin HEI Modules are all unsealed. The 8 pin HEI module is sealed for power, tach, & coil, but not for the pick-up assembly.

There is a module shown on the Performance Distributors modules page that they refer to as "Vortec" that I am not familiar with. It could be sealed for the pick-up wires and it may not be. None of the pictures that I've seen of it so far have been much help in sorting that out.

The vortec mid to late nineties had a remote module mounted next the ignition coil, passenger side along intake manifold,, both connectors are sealed type ,,

 

[ntsqd]

That part I'd discovered, but looking at the wiring diagrams for it, it appears to be more of amplifier or timer-relay than a stand-alone ignition module.

 

[DirtDonk]

I noticed that it has four pins within that weather tight cavity. Didn’t look up any images that might’ve shown the different sides, but from what’s being said, it sounds like that’s just a single connector with four conductors.

And when it comes right down to it, I don’t think that pin or connector corrosion has ever been a big thing. Maybe in harsher environments?
That said, I’m a fan of weather tight connections!

 

[ntsqd]

I don't have the diagram still up, but only one of those 4 pins is some sort of input. For an inductive pick-up to work it would need two of the contacts. It might (?) trigger from a set of points, dunno. I generally have a very large resistance to anything using points again, or it may be for the output from a Hall Effect system. Either way it's of no interest to me.

Living within a couple miles of the Left Coast has made me well aware of corroded connector contacts. If I lived in, say Central OR's High Desert, I might not ever even think about it.

 

[Bronk74]

Glad it’s running. It’ll be super interesting to hear what they find. If anything!
I mean, we know there’s something wrong with it. But will they be able to find it?
Time will tell…

We will see i work for fedex so shipping it to then is extremely cheap...ill roll the dice see what they find ...if they find nothing ill be completely baffled at this point lol

 

[EPB72]

That part I'd discovered, but looking at the wiring diagrams for it, it appears to be more of amplifier or timer-relay than a stand-alone ignition module.

Correct , coil driver module would be another name some parted books would have called it at control module ,, the vehicle would have a cam and crank sensor ,, the pcm sends a square wave for timing control on the white wire (B pin) ,, .. I thought there was another slightly different application but not finding it ,, guess have worked on too much stuff ,,

 

[gr8scott]

The hype mostly is due to the module, which is easy to use with a D-S II distributor.

 

[ntsqd]

Like that.

IF you're going to twist the wires like that diagram says, include the black wire too. Just don't connect the loose end to anything.