Hi if im going back to using the stock dizzy (previously was using electric) if i use a gt40r coil will i still need to put the resistor back in? and if so how would I wire one up?

can you buy the resistors brand new?

Cheers,
Tom

gt40r requires a resistor (the r in the part number is to indicate that, I'm not sure if any other coil brands use that but the gt40r definitely does) so it will work

Yep - teh resistors are available new.

To wire it up you will find that there are currently a few wires on the coil. 2 will come from the distributor, take those off and lift the distributor. There might be another one that goes from the coil terminal to the coil clamp/bracket and there's a capacitor on it. Remove that (actually if it has one, remove it and see if the electronic dizzy works better!). The stock points dizzy has a capacitor on the side of it, keep that one (or better still, replace it when you replace the points themselves, as a set, it'll cost you around $15 for new points and condenser (which is what the capacitor in this case is called)

There should be one wire coming off the dizzy. That goes to the negative "-" terminal on the coil.. There should be 2 wires now hooked up to the other side of the coil. If there is only one, you'll have to trace it back to see where they joined in the second wire. It's probably just joined at the coil itself. separate those two wires on the + terminal of the coil, take them off the coil. Now use a test light and switch the ignition on. Only one of the wires should have power. whichever one does, you plug into one side of the ballast resistor, and then run a wire from the other side of the ballast resistor to the coil "+" terminal. That second wire (which shouldn't have power going to it with the ignition on, and will only have power when you turn the key all the way to the 'start' position) goes direct onto the coil "+" terminal.

The idea is actually very simple. When the ignition is on, the main power goes through the ballast resistor to drop the voltage down to about 9v. This will be the voltage the coil sees and it will work fine like that whlst the engine is runnin, and the lower power helps the points to last longer. But for starting, you want the strongest spark possible. And not surprisingly, higher power on the low voltage side of the coil just prior to the spark event gives higher power on the high voltage 'spark' side when the spark is triggered. Anyway - to get that full 12v power, all they do is run an extra wire, either from the ignition key, or some other cars use a second wire from the starter motor itself) and when the key is all the way to the 'start' position, they send a full 12v down that wire, avoiding the ballast resistor, and strongest possible spark for better starting. As soon as you let go of the key and it springs back to the 'on' position, that extra wire has the power cut off, so it is once again powered 'via' the ballast resistor, dropping off the power going through hte low voltage coil/dizzy circuit and helping the points to last longer (the condensor is another thing that helps the points last, and if you ever change the points and they burn out in like a few months, you can bet good money it's the condenser that has failed. So it makes good sense to change both at the same time.

I have to be like a broken record and keep going back to saying that you should really strongly consider sorting out the hei dizzy you have, as they absolutely KO even the best points dizzy on its best day. They provide better starting, more low rpm smoothness (esp in cold climates or during winter) better throttle response, you name it, they do it better. Every person I've ever been around that has swapped points for hei ignitions has all said (after the first drive in it) that if they knew how much better it was, it would have been one of the first things they did when they bought the car!

Hi John,
thank you so very much for your extremely clear instructions! I really really do appreciate it!

I'm having troubles tracking down a part number for the ballast resistor.. In the process I have also found out the car is using the wrong coil with the s2 bluebird dizzy.. someone has kindly offered me one so that I can test it out with the right coil to see if that is my only problem.. If it is i would more than likely keep the s2 dizzy but i am still going to buy all the stock points based dizzy items to keep as I would like a spare..

I have now printed your resistor post and added it to my folder of useful information!

would you happen to know the part number of the ballast resistor.. i called repco yesterday and they politely searched then indicated they didn't know what i was talking about..

Thanks again John.
Tom