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I would like some advice. I now have a standard 67 289 with a hipo dual point mechanical advance distributor. Should I put on a pertronix kit, get a unilite vacuum advance type, or get a stock vacuum for the 67? The points are worn and I want to upgrade. This is a daily driver.
 

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I am a firm fan of the Petronix ignitor. I have not tried the ignitor II, which is the second generation of the Petronix. What this does is to eliminate points, which eliminates setting the dwell and point gap. No more burnt points or arcing points, etc. The installation is simple and also hidden. Completely stock looking. YOu can also upgrade your coil and not worry about arcing the points. As for the vacuum advance, I've read about externally adjustable vacuum advance cannisters, which sounds pretty good in concept, but I was running a stock dual diaphram NOS unit on my 70, until substituing a MSD dist., which is all mechanical advance.
 

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I'll try to summarize my thoughts...

Dual points: At one time to be believed they created more power through more or hotter spark, more accuratley delivered. Found not to be exactly true.

Mechanical advance: Ensures very accrate advancing of ignition timing, ensures high degree of consistancy. That much better than a vacume? Doubtfull. Easier to set advancment, yes, but with alittle knowledge and patience, a vacumme will work almost as well as a mechanical (in street application, racing is another story).

Pertronix: A good kit for converting and eliminating points. No more, no less. Want more power, go with a Crane Fireball setup. Mallory makes a similiar unit, but I'm partial to Crane.

My recommendation, keep your OEM distributor, unless you're planning on going racing and turning more than 6700 rpm, it will do ya just fine. Points- there are nothing wrong with em, I would recommend Blue Streak made by Standard Ignition, this is what they use to run in NASCAR in the 60's and early 70's. If you must change to electronic, just swap em out as suggested above with the expectations for performance.
 

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I had no luck keeping points after a 6500 RPM run. Droped a unilite conversion and it ran great. Later installed a pertonix and it ran just as well. I went with the pertonix because the thought of the light bulb going out in the unilite VS the posibility of permenate magnets going out in the pertonix. Didn't have any trouble with either, points stink!
 

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Since it's a daily driver, I'd definitely go with a vacuum advance unit, stock or otherwise. You should gain mileage and driveability with it. I've used both the Unilite and Pertronix. The Unilite requires a non-standard rotor, and needs the resistor wire intact as well. The Pertronix uses a standard rotor and does not want the resistor wire. Both work fine if you work around their peculiarities.
 

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Dual points. The key to this is understanding what "dwell" means. Dwell is the time the coil has to "charge" up before a spark discharge. It is measured in degrees of cam angle. Clearly the available time varies with rpm, going down at high rpm. Thus, as rpm increases, actual charge time decreases and this impacts the coils ability to fully charge at higher rpm. Hence, conventional coil ignition systems start petering out at 4000 rpm and above. There are ways of dealing with this problem:

Before the days of modern electronics, the ways to make a coil work better (at higher rpms) was:

* Wind a better coil - there are limits on what can be done

* Increase the dwell - add a second set of points or use two four lobe cams and two sets of points. (Mallory Dual Points and Mallory Rev-Pol). Note: Dual Points increases the rpm range about 15% and dual cams increases it about 40%.

Both these methods worked but had limitations. Modern electronics does the same thing but better. Whereas Dual Points extends the dwell to 35 degrees, Pertronix extends it to 40 degrees or so (45 degrees being maximum for a eight lobe cam or trigger).
 
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Thanks for all the good advice. I think I will go with the pertronix dual point kit and try it out.
 
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