Vacuum Advance Distributor for '73 Charger 318

[Strykr73]

I was at the Mopar Nationals in Carlisle recently and had some opportunities to talk to other Charger owners, particularly some mid 70's owners with 318's like mine. One interesting and disturbing revelation is that somehow, throughout its life, my car seems to have had its distributor swapped out. Normally that wouldn't be a big deal, but the distributor that was swapped in does not have vacuum advance. All model cars at this point in time would have had a vacuum advance distributor installed from the factory. I confirmed this with one of the other '73 318 owners who was there at the nationals, albeit their car had the 4-barrel 318.

So my question is...
Which distributor can I swap into place of the existing one without having to modify anything else in the system? The car has "electronic ignition" from the factory with the firewall-mounted voltage regulator and ballast resistor. It also has a separate ignition coil mounted at the rear of the engine next to the distributor. I've taken some pictures.

What I'm looking for is just a distributor to drop in place which has the vacuum advance on it. I am open to replacing the coil if needed, but not removing it.

Do I even need to worry about this? She runs fine as she is now, just without any top-end power. Suggestions, recommendations, and questions welcome!

P.S. At the same time, I'd like to add a tachometer to the car, so making sure the distributor and coil are compatible with a tach is a must. I picked out This One as at least a temporary solution. I find that having a tach is incredibly helpful in doing diagnostics. It's bizarre how all modern cars have them, but rarely need them, and antiques rarely had them and definitely need them!

 

[Cranky]

I'm thinking it has mechanical advance? Had an aftermarket one in my 70 383 Challenger and it worked fine. Put a timing light on it and see if the timing advances when you rev it up a bit.

 

[turbine68rt]

Is there an open window in the housing where the vac advance would be mounted? Maybe a PO didn't reinstall it.

 

[diesel_lv]

I'm thinking it has mechanical advance? Had an aftermarket one in my 70 383 Challenger and it worked fine. Put a timing light on it and see if the timing advances when you rev it up a bit.

All distributors w vacuum advance also have mechanical advance. The mechanical advance brings the engine into power range, vacuum then adds timing for cruising and better economy. This is a simplification but a general idea.

 

[Cranky]

All distributors w vacuum advance also have mechanical advance. The mechanical advance brings the engine into power range, vacuum then adds timing for cruising and better economy. This is a simplification but a general idea.

Yup....but you can get distributors that have mechanical advance only. Had the Accel dual point mechanical in my Challenger and had a Mopar tach drive mechanical electronic in a 68 road runner drag car. I've also seen stockers that were converted to mechanical only but never did that.

 

[70chall440]

Just putting it out there but I believe that the late 70's lean burn engines were computer controlled and did not have a vacuum advance.

There should not be any problem finding a replacement if want one as vacuum advance distributors were used for many years.

 

[PurpleBeeper]

Short answer - any '72-'75 small block electronic ignition distributor (double check those years).

Related to the other discussion...weren't the lean burn distributors completely locked out mechanical advance and not vacuum advance either? Just the lean burn computer doing it all ??? (I'm not sure)

 

[Darter6]

We have a member here that goes by halifaxhops. He specializes in Mopar distributors.
Do a search and you will find him.Great Guy.

 

[Strykr73]

I wouldn't be surprised with the emissions controls all over this car that there would be changes made to the distributor, but not including vacuum advance seems like it would be counter-active to that.

(...) I believe that the late 70's lean burn engines were computer controlled and did not have a vacuum advance.

There aren't any modules connected directly to the distributor, although I think I'm imagining the voltage regulators they put on the side of these things. I can looka round but I'm not sure what I'm looking for. There only seems to be one set of wires coming off of it and they got to the coil.

Is there an open window in the housing where the vac advance would be mounted? Maybe a PO didn't reinstall it.

I don't see any holes or missing parts.

 

[turbine68rt]

Any kind of label, part number, or brand markings on the housing?

 

[bolson6333]

There only seems to be one set of wires coming off of it and they got to the coil

do you mean one wire to coil? sounds like a points distributor. best pop cap off and look. also I think lean burn dist. had two pickups in them. If I remember right

 

[bolson6333]

And looking at your pictures I see no ignition box is there one

 

[Strykr73]

And looking at your pictures I see no ignition box is there one

I've never heard the term "ignition box" before, so I'm not sure what that is. Can you explain what it is or does so I can try to find it?

Any kind of label, part number, or brand markings on the housing?

I don't see any part numbers or markings on the distributor itself. Not without taking it off, that is. There could possibly be something on the back side that I can't see but there's nothing around the front anywhere I can see.

 

[Strykr73]

Here's another look at the coil. It has two wires coming in and one going out. If I understand this properly, the green is the negative and the brown is the positive.

Also apparently I was wrong and there is a part number on the distributor, but I still don't see a manufacturer name

 

[jimt1971rr]

You might want to check out Summit Racing. That is where I got mine and it works great.

 

[YY1]

I think I see a vac advance diaphragm in one of your pics.

Don't have the resources to photo edit a red circle and repost.

...but I bought a reman distributor for my 73 from advance auto parts and it worked well and is still installed after 6 years.

 

[YY1]

...and no lean burn until 1978-ish.