Looking for a 12 Volt Switched Source on '67 Mustang

[Greg]

First I want to say thank you to everyone for the DuraSpark ignition upgrade info. I was able to get all the parts I needed from a local parts store and make up my wiring harnesses using towing connectors (their water resistant and I couldn't find a salvage yard near me with a Fairmount).

I only had one problem when starting the car after installing the new distributor and ignition system. I only got a spark when I first started cranking the engine and when I stopped cranking the engine. It turns out the switched 12 volt source I used drops out when the ignition key is turned to the crank position. To make sure everything else was working I connected the ignition module's power lead to the coil's possitive lead (I know its only 6.5 volts) and the car started right up and I took her out for a test drive.

Now I've gone searching for another 12 volt switched source, but have yet to find one that doesn't drop out when cranking over the engine. The wire from the ignition switch to the coil on the '67 as far as I can tell has the resistor in the switch (let me know if I'm wrong for '67). So I can't connect in before the resistor.

Any one know of a good switched power source? Or should I just run the module off the 6.5 volts from the coil. Is there a down side to using the coil power source?

Thanks,
Greg

 

[nitrousnick]

hi !! what you need to do is run a wire from your starter solenoid to were your 12volts go to for your ignition.there will be an S and R terminal on your solenoid ,run a wire from the R terminal to the 12v wire all ready there,now when the solenoid engages the starter it will provide 12volts to that wire with no voltage drop .what you will have now is 2 wires powering your ignition ,1 providing 12volts when cranking with no voltage drop.the other one powering the ignition with the key on run.

 

[Greg]

Without a Diode/relay to prevent the back flow of power to the starter solenoid terminal won't the 12 volts from the wire connected to the original 12 volt source also continue to power the starter solenoid?

Greg

 

[nitrousnick]

no that wont happen , but I made a mistake the solenoid is labeled I -the factory system worked the same way except it had points -you need 12v when cranking with points and that is all that terminal does.