I have a 632 bbc with 18 degree dart heads and alcohol injected.No nos just naturally aspirated. I'm just trying to get some ideas on timing

28

our 632 18 degree motor runs best at 29 degrees on motor

30

Every engine is a little bit different. You are getting ballpark suggestions as a starting point. Without putting the engine on a dyno, you will never know exactly what the engine wants. After setting the timing, no other performance tuning (jetting, plug gaps, tire pressure etc) will change where the engine wants the timing,

Prob 29-33. Have to try and see what yours likes best.