Hestitation, strange timing issue.

[Darrman]

I had my truck running great for awhile a month ago, ran smooth, great power, no problem. Then I knock the condeser loose in the new rebuilt distributor, still dont know how, ran like crap till I replace it with another new rebuilt dist. Now the strange part, I had the timing set to 8 degrees with the first dist., but this new one will not run right till you crank it to 10 degrees. Like this it runs great, idles at 650-700 in park and 550 in drive. It revs up fine in park, but then when you are driving around and you stop or slow the idle all the way down to 550 again, it starts sputtering when you try to give it gas to go again. Once it is back up to about 700+ rpm it will run great again, real strong.
The dist. is a factory points unit, and the gap is right, cant see anything wrong with it, but why the change in timing?
Please help!
Thanks!

[fordman]

was it a rebuilt dist from the parts store or a used dist from somewhere? if it was new fromt he parts store that woudl kind of explain it. everything is tight. like the braker plate springs and weights. so it will be more true as far as where thetiming should be at with your current engine. so you will have to readjust your carb to run better with the new dist. but i could be wrong.

[Darrman]

They are both orielly's rebuilt units, brand new. I hand spun each before installing them, just to check for play and such, they both felt fine, same as each other.

[fordman]

i meant the weights and spring under the point breaker plate could have been worn on the old dist and when you ut the new dist in withne weights and springs it made the dist correct so the timing is now off. unless you got the dist off by one tooth when you put it back in.