FYI, you can usualy run anywhere from 8-14 initial time on these engines. Check you total advance and see how much is in the distributor. 36-38 is pretty much max.

I've been running 14/38 in my stock 383 and it has done well but I'm considering going back to 10/34 since I just cruise around. Engine seemed to be happier with that setting, ran smoother I think. Gas mileage isn't any better with the extra timing either so...

Be sure to run a lead additive if you are unsure if the heads have been updated with hard seats and make sure to run oil with zinc or you will most likely wipe the cam. You can get an additive or Valvoline ZR1 has it in there already. One of the few like that that the parts stores carry. Might have to have them order the kind you want if you don't want 20W-50