Crab conversion - how to connect external coil?

Walton Feep

Walton Feep

Member
I am converting to a crab distributor from a helmet. The system is 6 volt positive ground. I have a Pertronix Flamethrower coil.

Question is, how do I wire the external coil? Where do I make the connections?

Thanks in advance!
 
WF,
Tell us, are you using points or a Pert module ? Depending on which 'door' you
choose you could be heading off a very high cliff or just a moderate high cliff, I'm
not jivin' you.
Charlie ny
 
Walton, go back and reread your 6/20 thread. The people giving advice have decades of experience and are seriously trying to help. I get that you want to diy, but don't ask for advice and then go against it. I know Charlie ny, had him rebuild my carb, and believe what he tells me. Disregard his advice at your own peril. He and Jim (Bubba) are not looking for your money. But you cannot do better than their work.
 
Charlie ny said:
WF,
Tell us, are you using points or a Pert module ? Depending on which 'door' you
choose you could be heading off a very high cliff or just a moderate high cliff, I'm
not jivin' you.
Charlie ny
Click to expand...

I forgot to mention, I am using points based on the recommendations of others on the forum.
 
FireEngineMike said:
Walton, go back and reread your 6/20 thread. The people giving advice have decades of experience and are seriously trying to help. I get that you want to diy, but don't ask for advice and then go against it. I know Charlie ny, had him rebuild my carb, and believe what he tells me. Disregard his advice at your own peril. He and Jim (Bubba) are not looking for your money. But you cannot do better than their work.
Click to expand...

I forgot to mention, I am using points based on the recommendations of others on the forum and I purchased a rebuilt crab.
 
WF,
Ok you are in good shape if you DO NOT use the Pert coil. It is my practice
to either supply an Echlin / NAPA IC 7 coil for 6volt applications or strongly encourage
my customers to purchase one, you won't be disappointed.
With pos ground be sure to connect the positive side of the coil to the
distributor (same terminal that the condenser is connected to) and the hot wire goes to the neg side of the coil.
The IC 7 coil has an internal resistor so you must bypass the Ford resistor,
this is a must.
I/we can thank Jim 'Bubba' Linder for guiding us thru the ignition swamp
and getting us on the happy motoring side of things..........a BIG shout out to Skip
Haney and George Mitchell as well.
Charlie ny
 
Walton Feep said:
I have a Pertronix Flamethrower coil. QUOTE]

If I understand what your doing don't believe that coil will work! Do you understand how to calculate the coil resistance required and what the resistance is for the coil you have? You have to have a coil that matches the circuit you are using it in.
Click to expand...
 
Charlie ny said:
WF,
Ok you are in good shape if you DO NOT use the Pert coil. It is my practice
to either supply an Echlin / NAPA IC 7 coil for 6volt applications or strongly encourage
my customers to purchase one, you won't be disappointed.
With pos ground be sure to connect the positive side of the coil to the
distributor (same terminal that the condenser is connected to) and the hot wire goes to the neg side of the coil.
The IC 7 coil has an internal resistor so you must bypass the Ford resistor,
this is a must.
I/we can thank Jim 'Bubba' Linder for guiding us thru the ignition swamp
and getting us on the happy motoring side of things..........a BIG shout out to Skip
Haney and George Mitchell as well.
Charlie ny
Click to expand...

Thanks Charlie!
 
Walton Feep said:
The resistor to be bypassed is between the ignition switch and the coil correct? Is it under the dash?

Thanks again!
Click to expand...

Yep. Should look something like this, the ballast resistor is the one on the left.
 

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This thread has me wondering what the difference is between a properly functioning helmet and a properly functioning crab? If the OP has a stock engine, why the desire to change the type of distributor?
 
Capt Kirk said:
This thread has me wondering what the difference is between a properly functioning helmet and a properly functioning crab? If the OP has a stock engine, why the desire to change the type of distributor?
Click to expand...

It's a 1941 Super Deluxe but it had already had an engine swap when I bought it. It has a 59AB from a truck. The crab was probably correct for the engine if not the car. I'm keeping the helmet and will likely have it rebuilt.
 
the crab is cheaper to buy parts, and easier to get on and off the motor. better unit unless you get a dud like in my crab thread!!
 
I mounted mine on the left water pump outside bolt. Seemed like a good spot, lots of airflow.
(sorry, don't know why pic rotates when posted)

THANKS! @JSeery
How did you do that? Tried and tried, to no avail!
 

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I mounted mine to the stock coil mount for a 46 flathead.
 

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