Type 21 = D5AZ-14489-H .. Ignition Coil Sleeve / Obsolete

HASELDEN BROTHERS in Hemingway NC has 2 = 843-558-2134.

GRIESEL MOTOR CO. in Okarche OK has 2 = 405-263-7242.

KLIMESH MOTOR SALES in Calmar IA has 2 = 563-562-3241.

WESLEY OBSOLETE PARTS in Liberty KY has 2 = 606-787-5293.

GREEN SALES CO. in Cincinnati OH has 28 = 800-543-4959.

 

Thank you, sir.

 

In defense of the red module, it is more sophisticated by far than the standard duraspark II. The Red module got used with the California emissions because the blue module didn't make a hot enough spark to fire the lean California mixture. A working, good condition Red box will run better than a blue one.

The technical difference between the two is dwell control.

The Blue module has no dwell control at all. It has an unchanging, static dwell, just like points. This is why blue modules are used with a ballast resistor or under-dash resistance wire feeding the coil. The dwell is set from the factory to match the needs of the OEM coil with the OEM resistor. Running a blue-grommet Duraspark box with a different coil or different resistor can cause either a weak spark or a fried coil / duraspark module. However, it is cheaper and simpler than the red module, which is why Ford used it on the vast majority of their Duraspark cars. Even without dwell control, is still "good enough" for most cars, and a vast improvement over points, even when used with the wrong resistor or coil. You can find them super easy in the junkyard or at any parts store.

The Red module has automatic dwell control. It monitors the coil current and adjusts the dwell on-the-fly, varying it with RPM. Because it detects and automatically adjusts coil current, it can be used with nearly ANY coil and WITHOUT a ballast resistor, just like the GM HEI module, and will ALWAYS produce a hotter spark than the blue module, even at CA-spec .050" plug gaps. Unfortunately, the red modules are nearly impossible to find in the junkyard, being only widely used on '77 California cars. New parts-store red modules cost twice as much as the more common blue modules, and often have to be special ordered.
Details on the red module here.

Wells # for the blue module: F102
Wells # for the red module: F109
Wells # for the coil that matches the blue module: C832
Wells # for the resistor-wire that matches the blue module & coil: F796
Wells # for the "odd" coil connector: 252

 

Wow, great info, welcome to FTE, what a way to make a impression. 1st post and you hit it out of the ball park.

I can not wait to see what is said next.....

 

That's interesting. I guess that's why I've heard some hot rodders looking for that red module. Does the GM HEI vary we'll like the red Duraspark?

 

Yeah, it does. The only thing the red Duraspark does that HEI doesn't, is retard the spark on starting. And it only does that if the white wire is hooked up, which a lot of hot-rodders just leave unhooked.

 

1978: The factory installed red modules were defective, 100's of vehicles clogged dealers service lots throughout CA as the POS was on D99 - Back Order Detroit. ETA was THREE MONTHS!

I was the back parts counter guy at Walker-Buerge Ford in WLA, called a wrecker pal of mine, had him put the POS on the wreckers hot line, said I only wanted them from 1977's.

I was able to procure about 20 of them, which were then installed on customers cars. When the POS finally arrived from FoMoCo, they were no better than before.

It took another month before we finally began receiving modules that actually worked.

D7AZ-12A199-A .. Red Module - Scroll down to the bottom of the parts catalog page...

 

The defective batch and backorder might explain why so many 78/79 California cars in the wrecking yard have a blue module, even though Ford was using red through '79. I bet some less scrupulous dealer guys with no friendly junkyard supply swapped in blue modules to get customers off their backs.
Given the choice between telling a customer their new, still under warranty car wouldn't be running at all for 3 months, or putting in the wrong part and sending them home immediately with the car maybe running just a little bit rough.... yeah.


To make the parts-mismatch situation worse, my Wells catalog lists the blue module as the correct one for all 78-79 Fords. It only shows the red module used after 77 on a handful of Mercuries and a couple Lincolns. So there's a good chance that for the past 30 years, mechanics have been calling their parts suppliers, asking for a module for a '78 CA-emissions Ford, and getting sold a blue module.
It's only the Wells catalog that makes that mistake, though. The BWD catalog has the correct years.

 

The blue module use different wiring than the red module.

 

Oh, shoot, they have different connectors. Guess the dealers couldn't just have just stuck blues in place of reds.

Red:Blue:

The wires themselves are actually the same: red igniton, green coil negative, white start, orange & purple distributor pickup, black ground. It's the tabs on the connectors that don't match up, which just stops you from physically plugging them in, unless you break the tab off.



When I put a duraspark on my '69, I didn't use any of the factory connectors, I just used spade terminals for everything, so I didn't have to worry about that.