Question On Wiring of Pertronix 1281 with Flame Thrower Coil on 57

I have had the 57 about 4 months. After reading threads about the Pertronix 1281, and decided to buy one and mate it up with a Flame Thrower coil. Learned one lesson-Received new stuff, removed distributor cap...There is a Pertronix 1281!! However, it is hooked up to a stock coil, which is hooked up to the resister right next to it. The threads, and parts suppliers, led me to believe that the "hotter" coil was needed. However, maybe that's not really so, as the car is running. Anyway, the instructions for the 1281 and Flame Thrower contradict each other. The 1281's-keep the resister. The coil's-by pass it. The coil is 1.5 ohm, and I think that is what the resister is too.
So, can I just leave the wiring set up as is, and attach the Flame Thrower coil exactly as the current one? The reason I thought this might be necessary is there are two wires leading from the top connector on the resister (I assume power out). One goes to the carburetor, the other looks like it goes to an electric fan that has been installed on the front of the radiator. I felt if I by-pass the resistor, that would negatively impact the those hook-ups as it think it would cut off power to those two wires. I called tech support at Pertronix, they are closed until Monday. Thought I would try here. I guess I could leave well enough alone. Just thought there could be a benefit to the hotter coil. If I can hook it up just as the stock, that would be perfect. As you might tell, I am below amateur when it come to electrical issues.
 
I have had the 57 about 4 months. After reading threads about the Pertronix 1281, and decided to buy one and mate it up with a Flame Thrower coil. Learned one lesson-Received new stuff, removed distributor cap...There is a Pertronix 1281!! However, it is hooked up to a stock coil, which is hooked up to the resister right next to it. The threads, and parts suppliers, led me to believe that the "hotter" coil was needed. However, maybe that's not really so, as the car is running. Anyway, the instructions for the 1281 and Flame Thrower contradict each other. The 1281's-keep the resister. The coil's-by pass it. The coil is 1.5 ohm, and I think that is what the resister is too.
So, can I just leave the wiring set up as is, and attach the Flame Thrower coil exactly as the current one? The reason I thought this might be necessary is there are two wires leading from the top connector on the resister (I assume power out). One goes to the carburetor, the other looks like it goes to an electric fan that has been installed on the front of the radiator. I felt if I by-pass the resistor, that would negatively impact the those hook-ups as it think it would cut off power to those two wires. I called tech support at Pertronix, they are closed until Monday. Thought I would try here. I guess I could leave well enough alone. Just thought there could be a benefit to the hotter coil. If I can hook it up just as the stock, that would be perfect. As you might tell, I am below amateur when it come to electrical issues.
The purpose of the resistor was to lessen the wear on points after the car started. This is not used with Pertronix. They are very clear on that. I put in a MSD in my '56 and bypassed the resistor. Works great. The wires are a big question. The coil wires have no relationship to the carb or fan. One wire is power from the ignition (and powers the Pertronix) and the other is the pulsating negative post. (Cyclying needed to charge the coil.) I think someone goofed up the wires. Pertronix will run with the external resistor but not to full output. The coil has internal resistance as needed. I hope this was helpful. How about a picture and color codes of the wires? It might help.
 
Here are photos of the current coil and "resister". The top red wire looks like it goes to the front of the car in front of the radiator where there is an electric fan. I assume it ties to the fan, but i can't tell The blue wire attaches to what looks like a choke housing on the passenger side of the carburetor.
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Here are photos of the current coil and "resister". The top red wire looks like it goes to the front of the car in front of the radiator where there is an electric fan. I assume it ties to the fan, but i can't tell The blue wire attaches to what looks like a choke housing on the passenger side of the carburetor.
The pale red wire on the coil is ignition power. This wiring has been worked on. If one wire goes to the choke (after market electric), the voltage to the coil can be less. This is a common mistake when adding a choke. The heavy red wire on the resistor is not orginal from what I can see. Go look at someone else's conversion. Calling Pertronix is a very good idea.
 

Hadderz

Well-Known Member
Yep, I'd say someone needed an ignition switched power feed and pinched it off the coil! Best to run a new wire to the fan and choke and leave the ignition its own.
 
Thanks for the insights Hadderz, I believe you are right. I am just guessing because what I know about electricity is limited to flipping on a light switch. I believe that who ever did the wiring mods, wanted the power to only run when the ignition was on. So, the power for those chock and fan is coming off the positive side of the coil, through the resister. The car is running fine with the Ignitor model 1281, the stock coil and the resister. I could just leave well enough alone. OR, I could do what most guys like to do, and monkey with it. I believe I could install the Flame Thrower coil, with the 1.5 ohm resistance, which should match the current resister. Ditch the resister, and attach the two aftermarket wires that were added directly to the positive side of the coil. I hope....... I spoke with a tech at Pertronix, either way works for them. I just can't figure out if there is any advantage going away from the stock coil and resister, to the Flame Thrower coil and no resister.
 

Hadderz

Well-Known Member
Thanks for the insights Hadderz, I believe you are right. I am just guessing because what I know about electricity is limited to flipping on a light switch. I believe that who ever did the wiring mods, wanted the power to only run when the ignition was on. So, the power for those chock and fan is coming off the positive side of the coil, through the resister. The car is running fine with the Ignitor model 1281, the stock coil and the resister. I could just leave well enough alone. OR, I could do what most guys like to do, and monkey with it. I believe I could install the Flame Thrower coil, with the 1.5 ohm resistance, which should match the current resister. Ditch the resister, and attach the two aftermarket wires that were added directly to the positive side of the coil. I hope....... I spoke with a tech at Pertronix, either way works for them. I just can't figure out if there is any advantage going away from the stock coil and resister, to the Flame Thrower coil and no resister.
Understand especially if you're not electrically minded. So is the coil a benefit, well I'm sure the manufacturer claims so!! The resistor was added for better starting as when cranking the engine the voltage would drop so the original coil was manufactured to work on less than 12volts for that reason. Once running the voltage would increase so the resistor keeps the volts at the coil lower. I think that these new colis use no resistor and work on less than 12v to produce a decent spark but also on 12-14volts to give a better spark! As you say, if its running and running well then theres no point BUT if you've brought the parts.......
 
Well, I took the plunge and tried out the new Pertronix coil, in place of the stock coil and resister. I found that the Pertronix Igniter that was already installed in the distributor was only hooked up to the coil, and was not attached to the resister. So, I changed the coil, removed the wire that went from the positive side of the coil to the lower electrical clip on the resister. The car started just fine, and ran for a sight moment and immediately died. Tried it several times. Each the same result. Strongly fired up immediately, then immediately died. I put the old coil back in, reattached all of the wires as before, and it started and ran. I think I will leave well enough alone, and when I have some work done later at a shop, i'll have someone who actually knows what he's doing take a stab at it.
Thanks for all of the info above.
 
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