383 Wont Idle with new to me 800cfm DP. Idles and runs ok with Edelbrock/AFB

I'm not going to speculate but, your car should idle with that carburetor. i have a .030" over 383, big valve 906 heads, 509 292 cam bumped 4 degrees, 383 torker intake, MP distributor, MSD 6AL Box and at present Holley 750 in my Dart.
it started out with a edelbrock 750 and we will not get into what manufacture is better. WOT seemed flat, i picked up a Holley 850 and set it up factory jetting and put in 3.5 PVs since my vacuum at idle is 5.5hg. she runs a bit fat but..... the ol girl likes it very much, had to move shift points from 5600 to 6000 because it was still pulling.
with that being said, i am putting a wide band in and tuning the 850 to the engine. Oh by the way, no holes drilled throttle plates yet.