[jsporte]

Hello all.

I have a question that's probably backwards from what is normally asked.

I recently bought my 14 year old his first car, a 1966 Mustang with the i6 200. The previous owner installed one of the cheap GM style HEI distributors, but it didn't allow room to use the power steering pump. For learning purposes (for my son) I've decided to take it back to a stock style distributor and coil and hook the power steering back up (we'll upgrade them in the future so he'll be able to see the difference).

My understanding is that we should have (for the original style ignition) a resistor wire from the ignition switch to the firewall to drop voltage to 9v. From the firewall to the coil we can have a normal wire.

Does this sound correct to everyone?

I included a couple of pictures, because you know how we car people are ;-P

Thanks everyone,
Jeff

 

[awhtx]

Yes, the high resistance Pink wire begins a short distance from the ignition switch to a connector at the firewall. On the engine side of the firewall it is a Red/Green standard copper wire to the coil.
The Pink wire is 16A under the dash in this diagram and on the engine side of the firewall it is 16.

https://averagejoerestoration.com/resources/mustang-wiring-and-vacuum-diagrams/1966-wiring-diagrams/66ignit.jpg

 

[jsporte]

Thank you, I appreciate it!

 

[kenash]

Welcome to the forum. You have a great model to tinker on and learn about it's operation with your son. Have you purchased manuals yet or CDs?

 

[jsporte]

Welcome to the forum. You have a great model to tinker on and learn about it's operation with your son. Have you purchased manuals yet or CDs?

Not yet. We still have some time before he's driving.

 

[CJM68GT390]

Love parent/child stories. And welcome.
I highly recommend that you get a print version of the Ford shop manual and electrical assembly manual. Plus a print version of NPD's catalog.

1965-1973 Mustang Restoration Shop Manuals Parts - National Parts Depot (npdlink.com)
1965-1973 Mustang Restoration Electrical Assembly Manuals Parts - National Parts Depot (npdlink.com)

 

[Caper50]

Welcome Jeff, congrats on finding a car for you and your son to share time with and tech him the kind of stuff he won't learn in school. Looks like a solid car you have there. Post up some shots showing the full car please. Mine is Tahoe Turquoise as well.

 

[Magnus]

Nice car

Since you're changing out the distributor you should know that the I6s have a specific carb/dizzy combo that need to go together in order to work right.

The original Load-O-Matic distributor is vacuum only, but it's a special vacuum signal that only works right with the right carb with a Spark Control Valve sticking out the passenger side of it. You'll need to make sure you have both the right distributor /and/ the right carb if you're going to go back to stock.

Or you could go with a newer (68+) stock points distributor or 70s Ford Duraspark electronic distributor and run them with any carb you want (except one with the SCV).

Just something to keep in mind since you never know what's been swapped out on these things over the last 50 years.

 

[Still workin' on my 66]

Did you measure the volts at the positive side of the coil with the key on? You are correct that it should go through a resistor wire. X2 on the info from Magnus. Over the years many parts have been mismatched. As mentioned, up to 67 the carb had a spark control valve, and the distributor had vacuum advance only, old technology. The old style vacuum advance canister was very flat. In 68 the carb had ported vacuum, and the distributor was modernized, with mechanical and vacuum advance. The newer vacuum advance canister is cone shaped. To add to your learning, along with other changes, the carb opening was enlarged in 69, from 1 1/2" to 1 3/4". There is a lot of technical info at fordsix.com. There is room for improvement with factory parts.
There is nothing better for a family then wrenching on a cool car. Good luck

 

[PonyCarMan]

Is your I6 one with California emission controls? Those had the dual advance distributors like the 68's and up. You still need to make sure the carb and distributor application match up. That's another reason the shop manual is so useful. Those parts are not as common as the V8 parts, but still easily available used. And the good news is they aren't very expensive.

The replacement vacuum advance diaphragms don't match the vacuum tube fittings very well, so be prepared do a little hardware store engineering to get a good seal on that connection. Since the only advance is vacuum advance, a good seal is a must.

You'll have a lot of fun with that car. My six is very driveable, even when the AC is running.

 

[jsporte]

Love parent/child stories. And welcome.
I highly recommend that you get a print version of the Ford shop manual and electrical assembly manual. Plus a print version of NPD's catalog.

1965-1973 Mustang Restoration Shop Manuals Parts - National Parts Depot (npdlink.com)
1965-1973 Mustang Restoration Electrical Assembly Manuals Parts - National Parts Depot (npdlink.com)

Thank you, I'll look in to them.

 

[jsporte]

Nice car

Since you're changing out the distributor you should know that the I6s have a specific carb/dizzy combo that need to go together in order to work right.

The original Load-O-Matic distributor is vacuum only, but it's a special vacuum signal that only works right with the right carb with a Spark Control Valve sticking out the passenger side of it. You'll need to make sure you have both the right distributor /and/ the right carb if you're going to go back to stock.

Or you could go with a newer (68+) stock points distributor or 70s Ford Duraspark electronic distributor and run them with any carb you want (except one with the SCV).

Just something to keep in mind since you never know what's been swapped out on these things over the last 50 years.

Thanks for the heads up. I picked up a distributor that was supposed to be a direct replacement, but I'll look in to it some more.

 

[Magnus]

The short answer is that if your carb has this:

Then your distributor needs to look like this:

At least to take it back to stock.

You just can't use that distributor with a different type of vacuum, and you can't use that carb's vacuum to run any other kind of distributor.

 

[Woodchuck]

There's nothing wrong with the Load-O-Matic system and it's far from "old technology". It timed the spark advance to a modulation of venturi vacuum (based on intake air velocity) and manifold vacuum (based on engine load). When properly calibrated it actually works quite well.

 

[PonyCarMan]

It works well enough that:
1. The 6 is very driveable.
2. Keep it under 60 and get 28._ MPG.

At least that's what mine does.