Ignition - Total Advance

[Quick 8]

Hello,
I am currently using a '68 points style distributor with the dual port (advance and retard) vacuum can. I am using a pertronix unit right now.

Does anyone know how much total mechanical and vacuum advance this distributor adds??

For instance, if i have the distributor set at 10* initial, what is the max vacuum and centrifugal advace that gets added to that at max advance?

Any help is greatly appreciated. Thanks.
-Jim

 

[fordconvert]

I would guess typical would be around 8-10 in the mechanical and another 5-8 in the vac but at this stage of the game its hard to tell what has been done over the years. The weights can usually be modded to give more or less advance and there are/were differnt vac cans for differnt applications over the years that would give more or less. Many of the single advance cans are adjustable but im not sure about the double ones. Best way unless you have a dizzy machine is to use an advance timing light and vacuum pump/gauge along with a tach and find out for yourself for sure. I have had 3 of the same part number dizzys from the same store come out as much as 15* differnt in total advance.

 

[Quick 8]

Thanks for the reply. I would normally agree about not knowing what has been done to the distributor in the past, but this is a new NOS piece that should have the original weights, etc.

That's why I'm looking for an idea of what the factory advance was in '68. I hope to get a better timing light soon so I can verify the advance. But for now I'm stuck with a very basic light that I can only use to check the initial timing.

Any help on what the factory advance was in a '68 200 mustang whould be greatly appreciated.

Thanks,
Jim

 

[fordconvert]

I only have a 66 book so cant help you with 68 specs unless they happen to be the same as a 66, there are 23 differnt dizzy's listed for 66 so maybe? An example of the numbers in the book C5DF-12127-C. They are all that format and start with C5 or C6, if you have a number like that I will check and post the info if its in my book.

With a basic light to check total advance you can used the existing gauge to figure out what distance on the pulley is 5 or 10* and mark the pulley with chalk or crayon off 40* or so and then with your standard light you just read your new marks to the gauge to get the total advance. Lets say that on the gauge the 0 and 5* marks are 1/4 inch apart, if you make a mark every 1/4" on the pulley you will have 5* steps. It gives you an idea at least.

 

[addo]

Might have been "Montego Man" (Jay?) who spec'd out the late '60s points unit. He found the rebuilt purchased, was so far from factory, it wasn't funny. Basically, the rebuilders must have been on crack. You wonder how many they get so wrong.

Regards, Adam.

 

[66 Fastback]

Here is the link Addo spoke about.
http://fordsix.com/forum/viewtopic.php? ... istributor
Keep in mind that the numbers stamped on the weights are distributor degrees. You need to double them for crankshaft degrees.
Doug