I am thinking of updating my 59a to a crab distributor instead of the helmet. I have converted the car to 12 volts, neg. ground and would like have a reliable coil/distributor. The old helmet distributors are pretty good if you are running 6 volts but not sure so much about going to 12 with them. I have been working on one that has a traditional coil converted to 12 volt but not having much luck with it. I would like to hear people who have done this and if it the results were good on going to the crab and using 12 volt components from members here. I am sure this has been done more than once. ( I do know about using the little button adaptor for this kind of swap). Thanks in advance.
i have done it both ways, using the 3 bolt cover with the speedway adapter, and switching the cover over to the 2 bolt made for the crab. either way works fine. the speedway adapter is found by many, me too, to need a little filing on one corner that hits... um.. i forget, i think the vacuum port. just check your fit. i used a post war ford coil rewound for 12 volts by skip hainey in florida. they need an external ballast resistor as skip will not wire them with internal resistance as they run too hot and risk reliability.
I have tried a couple of skip coils and various combinations of resistors but am not having good luck there. I was about to try the adaptor plate and a more modern coil and condenser then I realized that I could go with a crab option to keep the look of a traditional flathead. Good to know about the adaptor so I would not have to replace the cover. Did you find that the OEM crab distributors were reliable for this and if so what condenser coil combo did you use? Wondering if buying a modern crab would also be an option.
what problems are you having? there really is nothing wrong with the helmut style performance wise, its just the crab is a little easier to remove, and has less expensive parts. i have 2 on running cars, but sadly not enough miles for me to brag about reliability yet. i had both rebuilt by bubba when he was more active, both are 12 v skip coils. there is a formula to determine what ballast to buy, then you go pick one out of the book at the parts store. there is a favorite condenser of bubba's from nappa. i have it written down here...some where.
I have used a helmet distributor in Ol' Blue for 20 years and it has performed excellent. I converted to twelve volts as well. The only issue is having to remove it to change points. I keep another one all set up and ready to go so the job goes quickly ( about 10 mins.). I have used the crab style in a different car and it behaved well also.
Thanks guys, I am burning up points very quickly. I was told to use a 1.5 ohm resistor which just did not bring the voltage down close enough at the coil. I tried a 2 and a 2.8 but still no go. I did check the resistance of the coils and they appear to be running around .48. Shouldn't they be higher like .8 or 1? I am guessing that even at .48 maybe I can run 2, 3 ohm resistors and solve this problem, what do you think?
The Jalopy Journal
