Installed Pertronix in Stock 351c - very poor starting and idling

[callys]

My 70 mach 1 still has an original single point distributor. I just rebuilt the 351c, and with the original distributor the car fired (on what seemed like the first crank amazingly every time) and idled ok.

A friend convinced me to install the Ignitor II from pertronix. I am using a painless harness, and I had a ballast resistor with the points.

I installed the pertronix and the car just doesn't want to start. I have 12.4v at the battery, and 12.4v at the coil with the key on hot. I have new wires.

If I crank the car about 100 times in the morning it will start, but will not idle unless I warm it up for several minutes.

I re-timed the car with the pertronix in to about 12 degrees BTDC at ~900rpm in park. I think that gives me about 10 degrees in gear. I do not have the vacuum advance hooked up at all so far on the new motor.

The same friend suggested moving the pertronix module closer to the magnet ring than their provided shim suggests. I did this, and its a little better, but still a pain to start, and will not idle until warmed up. Once it is warmed up it will run and drive all day.

If I put the points back in, the car starts immediately. I am really stuck and would like to hear ideas at this point. Are pertronix just not that great? Am I much better off with a duraspark?

Thanks everyone

 

[callys]

Now that I do more searches, I am finding several posts saying the pertronix needs a rewire to get a good 12v, and with the factory tach this is even more complicated. Does the same go factory electronic ignitions like the duraspark?

 

[Hack]

You want 12V for Pertronix. IIRC if you tap into the pink wire on the steering column you will get your proper 12 volts that you need. Every time I've gone from points to Pertronix I've gotten a boost in performance and fuel economy. Now it's one of the first things I do when I pick up a points vehicle. Well worth the upgrade in my opinion.

 

[woodsnake]

Did you check Pertronix's home page? I know they have a FAQ section..