[DanEC]

I will digress from Patrick a little - if this engine has a healthy cam and the distributor doesn't have vacuum advance, I would run the blue or purple bushing. I would try to run around 15 to 16 degrees of initial advance. I had Tim O'Connor set up my 427 dual point distributor and I it has 22 crank degrees of centrifugal advance and then I run 16 degrees initial (but I have low compression steel heads) for a total of 38. This will give you a stronger idle, help keep the engine a little cooler in traffic and make starts a little less of an issue.