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Just installed a PERTONIX II IGNITOR in my 68 mustang 302 2 bbl.
WOW! What a difference. Smooth throughout the whole RPM range.
Idles beautifully, only problem is a minor hesitation on take off. I am assuming to much timing?? Probably wrong,.....I'm always wrong.

The motor is installed in a 1963 Ford Fairlane 500. The car is a daily driver, driven both City (downtown Chicago)and Highway.

I do not need another tire burner, for that that I have a '05 Mustang GT with Twin turbos. (Yup, I was bragin!)

Here is my Questions??

1. What is the recommended spark gap
a. stock
b. for my set up.

2. What is the timing setting
a. stock initial and [email protected]
b. what would you recommended for my set up
stock and dwell @ RPM

Feel free to post your answers and any added comments or suggestions.
Thank you , Intruder
 

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Registered
Joined
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1,806 Posts
Just installed a PERTONIX II IGNITOR in my 68 mustang 302 2 bbl.
WOW! What a difference. Smooth throughout the whole RPM range.
Idles beautifully, only problem is a minor hesitation on take off. I am assuming to much timing?? Probably wrong,.....I'm always wrong.

The motor is installed in a 1963 Ford Fairlane 500. The car is a daily driver, driven both City (downtown Chicago)and Highway.

I do not need another tire burner, for that that I have a '05 Mustang GT with Twin turbos. (Yup, I was bragin!)

Here is my Questions??

1. What is the recommended spark gap
a. stock
b. for my set up.

2. What is the timing setting
a. stock initial and [email protected]
b. what would you recommended for my set up
stock and dwell @ RPM

Feel free to post your answers and any added comments or suggestions.
Thank you , Intruder
1. a, .034" b, as small a gap as you can run with a smooth idle.
2. overall timing (with vacuum advance disconnected) should be 34 degrees at 3500 rpm. Be sure to re-connect your vacuum advance after setting the timing.

You cannot change the dwell when running a pertronics ignition - it is set by the relationship of the two poles on the pickup. see the above for what is recommended for your setup.

NOTE:
In spite of what you might hear a smaller gap is always better for both performance and economy. If you are interested in WHY then read on.

A coil will produce only the voltage needed to jump the gap and resistance in your ignition system. A coil ALWAYS produces the same amount of power (watts) Volts x Amps = Watts. Amps, not volts, is what lights the fire in your combustion chamber. The lower the voltage the higher the amps from your coil - bigger gaps requires more voltage and LOWERS amps. Higher volts also degrade wires, rotor and cap. The higher the volts the more voltage leaks through the insulation.
There is one caviate here; If you are running a capacitive discharge (CD) ignition system Electronic with an amplifier box (dura-spark) then you can use a larger gap BUT the rule is the same, you get a "HOTTER" spark with the smallest gap you can run.
"If that is true then why did Ford and all the other manufacturers go to big gaps?" Remember when the gaps were at .060 and .080"? They increased the gaps to make sure they could ignite lean mixtures. They built entire ignition systems so they could get enough power to the plugs to jump those gaps! The ignition systems are better BUT unless you are running very lean mixtures (not likely if you have replaced your carb) then you might need to run bigger gaps to light it off. If you are running an aftermarket or performance carb you will not need those bigger gaps. You will get better high RPM performance and better all- around performance and economy running the smallest gap that will produce a smooth idle.
On my SBF engines I have found that a gap of .028" - .030" is the best. The sixes run better with a gap of .030" - .032" because they have a less efficient combustion chamber. Some of the aftermarket heads (AFR 165 for one) will run superbly with only a .025" gap.

The only way to know for sure is to experiment with your engine and see what works best for you.
Yes, I know there are those who say their engines run better with a .045" gap - it is probably true. But remember, no two engines are alike and you should experiment to find out what works for you.
 
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