centrifical advance question

[kirkallen143]

Howdy All,

Asking about the so-called cam that the points open/close on, where the advance weights sit there is a 15R slot and a 10R slot, and it looks like you can change them so the centrifical adv is limited with the 10R slot (it was previously on the 15R slot). 'Cause with this turbo application I am only looking for a total of 24* adv. max (say 12* initial and 10* by centrifical). Am I right/wrong, Thanks fellers.

Kirk '73 bronco

 

[mustang6]

You are right about the function of the slots. Don't forget to add your vacuum advance into your equation (unless you are not running vacuum advance).

 

[Anonymous]

10R = 20 degrees mechanical advance. The slots are always 1/2 the true mechanical advance due to the crank rotating twice for every one rotation of the distributor.

 

[kirkallen143]

Again Gentlemen, you have proven this one of the very best forums around. Thank you.

Kirk ' 73 bronco

 

[Does10s]

Kirk,
Weld the 10R slot 50% full. You'll get the 10* adv. swing that way.
It works fine.
Later,
Will

 

[kirkallen143]

Will,
That sounds easy enough for me, I was wondering how your's was done in the first place and I thought that might have been the coulpret. Like you, can get that high initial adv., but with the "Super 60" and .48 turbine housing I don't think off the line should be any problem w/ this 200. At least I can change to the .63 turbine housing for minimal $$'s if the top end gets too flat too fast. But it is not a drag racer, so ought to be just fine...just fine. All I lack is the 3 angle valve job, everything else is ready to go (estimate about 3 more weeks for start up), CAN"T WAIT!!!!!

Kirk ' 73 bronco

 

[Does10s]

Kirk,
Our's is setup with 17* initial and a total of 27*.
We normally run this setup with 106 octane in the tank. But we've run it with 93 without any trouble.
So start out easy and creep up on the tune!
And post some pics!
Will