Check to see if your vacuum advance is working properly. When you rev it up slightly, the distributor should move. If not check the vacuum lines to see if you have vacuum to the advance mechanism. If you have vacuum and it still does not move you need a new advance. You can also check it with a vacuum pump.
Fred


1956 3100 Pickup/Red/350/3sp OD/PS/Disc Brakes
1957 Bel Air Sport Coupe/Red/355/TH350/PS/Disc Brakes
2017 Silverado LT Single Cab SB/Black/5.3/6 Speed Trans
1947 Willys CJ2A w/F-Head engine