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

[Tim Shea]

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.

[1957Birdman]

I would leave things alone, assuming the car runs fine. Unless you are going to drag race your car I doubt that you will notice much of any difference in normal driving. I have had a Pertronix in my car for 24 years with the same wiring as original without any problems. 

Best regards.

Lew Bachman

1957 Thunderbird Colonial White

[paul2748]

I think the Pertronix instructions say you don't use the resistor with their coil.  I got the # 2, and tht is what my instruction say.  Check the instructions.

[edinmass]

Doesn’t matter how hot a coil or spark the engine has in your application. The standard factory ignition system probably exceeds the requirement of the engine by 500 percent. Personally, I would remove the electronic ignition and run stock. I’m not a fan of electronic ignition systems in cars that didn’t have them new. Hundreds of millions of cars ran fine on points, and drove billions of miles, without any problem. They are serviceable on the side of the road. The only tool you need for a Pertronix is a tow truck.

[1957Birdman]

Ed, I understand where you are coming from and I am not generally a fan of deviating from what came with the car originally. One of the things I like about the Pertronix implementation is that other than an extra wire it is not obvious that there has been any change from the stock setup. I see the advantages of the Pertronix as follows:

• Never have to set the points or dwell
• Clean installation without any extra boxes under the hood
• Easy to go back to points and condenser if necessary (I carry mine with me in the trunk just in case)
• No points to get pitted and wear over time.
• Better gas mileage

The only time my car has really croaked on me it was because the fuel pump went bad. I have put 25K miles on the car with no problems with the Pertronix. Of course as soon as I say this I will probably have problems. Hopefully not.

Lew Bachman

1957 Thunderbird

[edinmass]

Lew, I get the idea. Carrying the old points plate is a good idea. I have driven over 50 years and only had one set of points fail......and the y were modern Chinese junk points in the car that was just acquired, And I was not aware they were installed. I had a NOS set in the glovebox, so it was only a fifteen minute delay. Stock is always the best choice. I have electric pumps in all the cars as a backup and to prime when hot. Recently I have seen a few new electric pumps fail right out of the box.

[Matt Harwood]

Ohm's Law (V=IR) says the voltage at the spark plug will be exactly equal to the amount of energy required to jump the gap, no more, no less. Even if you have an ignition system that can make 1 million volts, you'll still only use enough voltage to make the spark. So in that regard, an electronic ignition does not make a better or hotter or more efficient spark. Spark is spark and it will only be enough to bridge the spark plug gap. More power can cover for things like bad grounds and a gap that's too large, but in general, putting a more "powerful" ignition system on a car does exactly nothing in terms of combustion.

 

An electronic ignition can, however, help the engine fire faster. We added a Pertronix to my wife's 1966 Mustang GT and it does fire noticeably faster. I only installed it because we were having a random stalling problem that I couldn't solve (ended up being the starter solenoid) and changing to the electronic ignition was one variable to eliminate. It worked well so I kept it. If the Thunderbird's ignition system is like the Mustang's, it runs on 8 volts. There's a resistor wire in there somewhere that steps the voltage at the coil down to 8 volts. Just attaching the Pertronix unit to the coil often doesn't work (it seems to work on some Mustangs but not on others). It seems to prefer to be fed a full 12V. You should find a switched source of 12V current. We used the ignition switch. Don't use the starter solenoid because it shoots a full 12V to the coil during cranking, but then reverts to 8V, so it will still confuse the Pertronix. Or maybe the T-Bird is different, I'm not sure in that regard. But it was an issue on many Ford products of the era and something to be aware of when installing a Pertronix unit.

 

And as Ed said, the electronic ignitions are fine until they fail--they give up in a millisecond puff of smoke with no warning and no symptoms. Points, however, will continue to work even in failure mode and get you home. An electronic ignition is not "more reliable" any more than it is "more powerful." But it does make some cars start easier.

 

Hope this helps!

[edinmass]

I agree with what Matt said above.......but would comment that the reason the car starts faster is the solid state timing set up when the engine speed is under 400 rpm’s. It’s possible to dial in a distributor to do the same. My estimate is that 98 percent of distributors are not functioning as designed due to being gummed up and worn. Often times ten percent of the engines power or more is lost to distributor sues.

[Tim Shea]

Well, I took the plunge and tried out the new Pertronix FlameThrower 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.

[1957Birdman]

I'm not sure why you want to change things if the car is running as it should. The start and die problem is most likely related to a faulty or miss-wired ballast resistor. I know I had that problem many years ago. I got a new ballast resistor and it fixed the problem.

Lew Bachman

1957 Thunderbird

[Tim Shea]

Yeah   I think i will leave well enough alone.  Had the parts so i thought i would give it a try.  

[Tim Shea]

Well I think I know what is going on and why the car died right after strongly firing up.  While I am far below amateur level when it comes to electronics, i think with  help from a fellow on another forum, this is what I have.  And, looks like someone did a bit of re-wiring and did not use the original wire colors and everything is in large wrapped up bundles , so it took awhile for me to unscramble.  I think this is what I maybe have going on. In the photo you can see a pinkish colored wire going to the + side of the coil. More than likely this is coming from the solenoid and that is why the car would start as I had attached that wire to the + side of the Flamethrower coil. The three wires attached at the top of the resistor include the power wire from the ignition. I believe that must be the lower wire of the spliced wires "Y" formed in the black covering. That wire is also supplying power to the choke, through the blue wire in the upper part of the "Y", and the red power wire going to the electric radiator fan. Plus it is sending power into the resistor. The black wire from the bottom of the resistor goes to the + side of the coil. This is taking the power from the the ignition, coming in from that lower wire (Ignition wire) in the "Y" at the top of the resistor, reducing the voltage, and then it goes to the + stud on the coil. That was not connected to the FlameThrower coil, which is why the car immediately stalled. Therefore, power coming from the ignition goes to the fan and choke before the power goes into the resistor.

I should be able to take the lower "Y" wire from the ignition and attach it to the + stud on flamethrower coil, along with the wire from the solenoid. That should have both wires to the+ side of the coil, the one from the solenoid and the one from the ignition. I can continue to take power from the ignition to power the choke and fan, as it is now., and no longer use the resistor. At least, that is what with my very limited understanding of electronics, I think should work. OR , like 57Birdman wrote, I could just leave well enough alone and not chance screwing everything up. Just hate to have a perfectly good new part (Flame thrower coil) just sitting in a box begging to be used. Seems like the change over was only 1/2 done.........if I am right with the above, I just need to decide if I should take the gamble. "To tinker or not to tinker that is the question..".

[Matt Harwood]

How does the manual say it should be done?

[Tim Shea]

The instructions do not really cover what I have because of the modifications.   I called the tech folks at Pertronix and they thought what I described would work but they too weren't 100% because of the wiring modifications.  I suppose the worse case if I make the changes and it does not work, Ii can put it back as it is now.   I have a spare igniter module  because I did not look before I ordered one  (another lesson learned).  I thought the points and condenser were still in the distributor as the stock coil and the resister where there.  Not so.  I even have a spare set of stock points and condenser.  So if I screw the current igniter up, i can put everything back the way it is and write the while thing off as a lesson learned even more....

[1957Birdman]

First off, I think you should keep the basic wiring the way it is and retain the currently installed coil, which is the correct one and style (yellow top) for your car. If you go with the Flamethrower it looks like you should bypass the ballast resistor since the coil has an internal resistor. The bigger concern I have is with the wiring of the choke and fan. I understand why it was done (it is a constant 12 volt circuit when the ignition switch is on). The problem is that I'll bet the the fan pulls more amps than the wire from the solenoid to the ballast resistor is designed for. I fact I'm surprised that wire hasn't melted some because of that. I think those items should be connected to the starter solenoid. Of course if you control the fan by a switch then it probably isn't so bad if you use it judiciously. 

When I installed my Pertronix I hooked the red wire to the positive coil connection and the black wire to the negative coil terminal. I didn't change anything else from the stock setup. Running that way I have put over 25,000 miles on my car without any problems. 

Regards,

Lew Bachman

1957 T-Bird