I have a 383 in my duster. It has a mopar performance/direct connection ignition in it. When i set total timing to 36 degrees, I get a miss above 2000 rpm at light throttle. When the vacuum is disconnected no miss. It seems like there's too much timing, or the rotor/reluctor phasing isn't correct. I have heard about a modified reluctor that corrects phasing problems. OR, with the 36 degrees total I'm running, is it just impossible to run vacuum advance too? Maybe cut down on amount of vacuum advance, are there cannisters that have different amounts (in degrees) of advance? somebody has to know the REAL story.

Or limit the vaccum advance.

here is a link that may help if you decide to go in this direction.

http://slantsix.org/forum/viewtopic.php?t=13198&highlight=vc208

Unfortunately, none of those numbers will work with a big block. Guess I'm going to have to do a little research to find a vacuum can with less advance than I have now. thanks for the post.

If the ignition was something that was purcahsed in the past 4 or so years the guts of the distributor are made by Mallory and the vacuum advance is adjustable as is the total mechanical. You can also use the Mallory 29014 kit to get a selection of springs to tune the rate that the timing comes in.