Duraspark II ignition

[c9zx]

Is anyone using a Duraspark II ignition system with a factory tach? Thanks Chuck

 

[Hemikiller]

Duraspark II distributor, MSD 6AL box and a tach adapter.

If you're using the Duraspark ign box, IIRC you can pull the signal for the tach adapter off the (-) side of the coil and it'll work fine.

https://jegs.com/i/MSD/121/8920/10002/-1?CAWELAID=1710552410&CAGPSPN=pla&CAAGID=15769068431&CATCI=pla-208406896871&CATARGETID=230006180037474382&cadevice=c&jegspromo=thirdparty&gclid=CjwKCAjw1tDaBRAMEiwA0rYbSC5XL5GX02tG4fRyyvTpCM7ISYZbdYJBlZ_LwqZSKfRe_WTyZ_saFRoCyiQQAvD_BwE

 

[stanger73]

I had The Duraspark setup on my 73 Mach I with factory tach. It worked great for years. I recently switched to the MSD 6AL and the tach adapter. Did you have a wiring question?

Sent from my iPhone using Tapatalk

 

[TommyK]

Duraspark II, TFI coil, MSD 6A box

 

[c9zx]

I had The Duraspark setup on my 73 Mach I with factory tach.  It worked great for years.  I recently switched to the MSD 6AL and the tach adapter.  Did you have a wiring question?

Sent from my iPhone using Tapatalk

How was the factory tach connected? I'm trying to help a friend come up with a duraspark system that works with the factory tach. The pertronix distributor that is installed won't clear the ram air set up. Thanks, Chuck

 

[stanger73]

The tach was connected through the factory pink resistor wire. The resistor wire provided the 1.5 ohm resistance that allowed the tach to read correctly.

I still have my wiring diagrams from when I rewired my car with a painless kit about 5 years ago with the Duraspark setup. Unfortunately, I am in Europe right now and wont be back in the states until the 1st of August.

Sent from my iPhone using Tapatalk

 

[Hemikiller]

Factory tach was fed from ignition feed, through tach, through resistor wire and then to the (+) side of the coil. It's a current triggered tach and sensed the cycles of the coil. The tach adapter replicates those pulses for the tach to work properly.

 

[c9zx]

Many thanks to all who posted. I now know it is workable if he decides to go that route. Chuck

 

[stanger73]

Did he end up going with the Duraspark setup?

Sent from my iPhone using Tapatalk

 

[c9zx]

He hasn't yet decided. I'll update when he does. Chuck

 

[Don C]

You can do a hybrid system, where the coil is connected to the OEM resistor wire, and with a separate switched full 12 volt connected to the power feed for the Duraspark box.

Here's a link to another thread on the topic, post 3 has a writeup (not mine) with two wiring diagrams, one to use a Duraspark coil and the other to use the reduced voltage coil.

https://www.7173mustangs.com/showthread.php?tid=27286&pid=274660#pid274660