Harmon Collins build thread ...

[BUBBAS IGNITION]

This is just the start of a thread on the Harmon Collins distributor build . I have 3-4 of these in the shop and have just stopped just to build these units . I will include a step by step blow by blow as we go over the next couple weeks .
I have done quite a few of these over the years and will include part numbers etc for different stuff.
So lets start with the WHY do you need a Harmon Collins dual coil set up for the flathead ????

And i guess you could answer that with you dont need it .

However there was a time when you could experience a gain from the dual coils etc. Lets pretend its 1944 or so and you have built your 50th flathead and each one you and Jed down at the Esso station had figured out how to make one run a much higher rpm band from stock . Assuming its 1944 there wasnt many options even with a small tow ignition guru with a old allen or sun machine .
I remember hauling a box of parts wrapped in a army blanket to another town and having some top secret work done (early 60s for me), put the heads back in the blanket then taking them back to the station . ( we ran a flathead on a local dirt track and the rules were stock engines , up to 53 ) Years later i began to understand that the out of town shop was flycutting the heads so the valves didnt hit the head!!!
So lets assume you do need it and think they LOOK cool !!
The Harmon Collins dual coil is a pretty simple unit utilizing tow seperate coils and acts as two four cylinder ignition systems utilizing a increased dwell time per coil firing event , ( so there IS a advantage ) Distributor cam is ground to provide four cylinder action thru the bendix aircraft platinum contacts !!! Platium high quality contacts are very reliable and may or may not need replacement .
SO FOR DISCUSSION SAKE LETS ASUME YOU DO NEED THE ENHANCED SYSTEM .......
SO LETS DISCUSS AS WE GO , I WILL ADD AS TIME ALLOWS ........

[42merc]

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[STAN WHITE]

Bubba I think I bought a couple of condensers from you for my Harmon& Collins dual coil ignitions. I also am going to run an H&C Ignition. I have one that I ran for years , That I will probly run again. I also have two new H&C in the box just incase. Interested to hear the rest of the story from you. I also like others info. Thanks. Stan

[JM 35 Sedan]

This will be a good one to follow. I think I had asked if you could do this for us some years ago, around the time you did the crab build thread.

[fortyonerag]

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[38 coupe]

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Just to be clear, it looks to me like the Harmon Collins unit is a reworking of the stock 42-48 V8 distributor. Is this correct? If so, I'm guessing that a really dedicated person could make the conversion parts today since there are plenty of stock distributors still around (not interested myself, I've always run out of bravery exceeding the speed limit before my stock drive lines ran out of acceleration).

[BUBBAS IGNITION]

A little sunday morning discussion , ( baby its cold outside at 2 degrees in Indy ) so glad i insulated this shop really well!!!
Looking at the unit on the bench the lower section below the line is the parts needed to make it the " Harmon Collins distributor . Someone asked if they could just "make" the parts , i would say "probably not" ...
From left to right

1- u shaped condensor mount to mount the condensors (one for each coil)
2-Point plate with Bendix Aircraft contacts mounted one set per coil
3-Cap clips ( 49-53 loadamatic )
4-distributor cam with everyother one ground off (machine ground )
5-Dual coil special rotor with carbon button on bottom
6-secondary ring with brass contact and secondary coil connection
7-Harmon collins ( no center bump inside ) also special cap assembly
8-two long screws to allow primary ignition hook up
9-upper left rotor adapter to allow special rotor to fit crab

We will massage and clean all these parts and adjust as we go .
Upper parts will be treated as usual........

[FLTHDCPE]

Do a search, both here & on H.A.M.B. Someone has already tried this. A lot of work and expense, and the results were not all that good.!! Ask me how I know.?

[BUBBAS IGNITION]

Ok some more work today :

One of the weak points on a collins is the plastics , think about it they are are at the least 50 years old . When new they used 6 volts and very low current levels ( maybe 4 to 5 amps at the most ) . One of the problems is what i call "chevrolet mentality" . Chevrolet mentality is when you and your "chevrolet " friend think that 12 volts and a .4 ohm msd super coil made Grumpy Jenkins Camaro run fast it should work on your early ford !!! And it will work at least for a little time .
We suggest using the Bosch blue coil from amazon .com # 00012 Bosch Blue ......

Heres a secondary ignition law for you ....

YOU CAN NOT PREVENT SECONDARY IGNITION FROM FINDING A PATH TO GROUND !!! EVEN IN A VERY OPEN CIRCUIT "IT WILL SEEK AND FIND A GROUND SOMEWHERE "
IF YOU OPEN CIRCUIT THE SPARK WILL TRAVEL THRU SOMWHERE EVEN THOUGH YOU MAY NOT SEE IT OR WHERE IT WENT .

So using those thoughts the other issue with these distributor is they often will only run on four cylinders . What we have found is that the secondary spark is grounded somewhere ???
To help prevent this we use GE Gyptal insulating paint , the holes for the coil screws are a great place for voltage to arch and kill four cylinders are treated with a coat of gyptal paint as well as the inside the distributor cap.
These parts are kinda hard to get but dzus on the board used to make some replacements . ( more about that later )

[BUBBAS IGNITION]

Another blip for today , amazon just dropped off some new Bosch Coils for this project .
Brazil made for German Bosch # 9 220 081 083
us # 00012 cost approx $50 each
3.0 ohms so no resistor needed
I have never ever seen a defective one !!!!
Can be mounted in any position, dont like the color paint them or use stick-um paper checkered flag etc ......

[FLTHDCPE]

It should look like this.

[Tim Ayers]

Originally Posted by 38 coupe

Just to be clear, it looks to me like the Harmon Collins unit is a reworking of the stock 42-48 V8 distributor. Is this correct? If so, I'm guessing that a really dedicated person could make the conversion parts today since there are plenty of stock distributors still around (not interested myself, I've always run out of bravery exceeding the speed limit before my stock drive lines ran out of acceleration).

Tyrell Pennington in Alaska is making new dual coil distributors using the rabbit ear style crabs. He goes by tradrod1930 on Instagram. They look killer.

[tubman]

The only thing that would improve that picture is adding a couple of proper condensers.

[FLTHDCPE]

I had two of your"proper condensers" on this distributor before these. I experienced an ignition problem and changed to the ones that are on there now. I sent you a "PM"

[tubman]

Originally Posted by FLTHDCPE

I had two of your"proper condensers" on this distributor before these. I experienced an ignition problem and changed to the ones that are on there now. I sent you a "PM"

I am in the process of answering your "PM". I don't think it would be proper to get into a discussion of what happened on the general discussion board as others are involved.

[FLTHDCPE]

Like this one better.!! This is what I like.!! "Ole Timey" Look.!!

[Als48]

I Got a hot rod Ford and a Two-Dollar Bill,

Ha ha

[STAN WHITE]

Bubba A few questions. First I purchased two of your Condensers they are very nice, Very satisfied. My question is on the Blue Bosch 12 volt coils. I understand that they are 3 Ohms and have a built in resister. I think above mentioned that a resistor is not needed with a 3 ohm coil. So I am alittle confused? Also where should I buy 2 ea Bosch coiles . Do you handel that? Plus looks to me that I might have to make a new brkt to hold condensers on a H&C Distributor.Does the length of the wire being longer should I stay with the same Gage? I have not ran this Engine since 1989. I was running it with a H&C Ignition I just bolted it up and it ran great. I might have been over doing it but it would go to 6K rpm No problem. !/4 X5 276 C I. Running a Potvin .425 Cam. Ed Bingly Engine. I also have two new H&C Distributors that I purchaed 35 Years Ago. Might be willing to sell one. Thanks for any info that you can privide. Stan White. 775 265 5333 Gardnerville,Nevada

[34fivewindow]

Originally Posted by STAN WHITE

Bubba A few questions. First I purchased two of your Condensers they are very nice, Very satisfied. My question is on the Blue Bosch 12 volt coils. I understand that they are 3 Ohms and have a built in resister. I think above mentioned that a resistor is not needed with a 3 ohm coil. So I am alittle confused? Also where should I buy 2 ea Bosch coiles . Do you handel that? Plus looks to me that I might have to make a new brkt to hold condensers on a H&C Distributor.Does the length of the wire being longer should I stay with the same Gage? I have not ran this Engine since 1989. I was running it with a H&C Ignition I just bolted it up and it ran great. I might have been over doing it but it would go to 6K rpm No problem. !/4 X5 276 C I. Running a Potvin .425 Cam. Ed Bingly Engine. I also have two new H&C Distributors that I purchaed 35 Years Ago. Might be willing to sell one. Thanks for any info that you can privide. Stan White. 775 265 5333 Gardnerville,Nevada

Here you go Stan

[STAN WHITE]

34 five window, Thanks for the photo brings back many memories! Ed was a good guy very knoelgable person I learned a lot from him. I went up to I think Windsor when he had his Willys there bought him a bottle of Brandy & a box of good Cigars. That was the last time I saw him. I miss talking to him. I have two of his Engines. It was amazing the extensive work he performed on the blocks when building his engines. Mainly on the end exhaust ports! I assume from your location that you know Vern Tardel. Any way I am doing an original 34 3WDW have had it for thirty five years. I looked for one since the early 50s. This car is special to me as it is perfect in every way. Original paint (Black) it has the original stripe in places. No holes drilled no rust. I am doing it as an early 50s car. Give me your e mail and I will send some photos. I was in the Richmond area in my younger days. Stan 775 265 5333