1966 Dart 225 with Holley 1920

Early a body said
bump up your timing . i run 8- 10 on slant six at idle not to exceed 32 all in mechanical , this will increase your rpm and vacuum at idle

I was leaning towards a possible issue with the timing, I'll try your suggestion, so that's 8 to 10 BTDC? I keep seeing different settings, one site says set at TDC for 60s slants another said 2 btdc.