[Rev]

I think somethings wrong with your timing advance curve. Set your initial advance at about 10-13 degees. From what you're saying, I'll bet you aren't getting anything after that. You can tell that with a timing light. Either the vacuum advance or the mechanical advance is not working. You can tell which one by disconnecting and/or connecting the vacuum to the distributor and reving to 3000 or so. If your not getting the required extra advance either from vacuum or from centrifugal advance, then you will know where work is needed. At 3000, you should have 30-35 degrees of advance.

Rev