Restoroddin

Ok here's the specs
all factory 371 rocket in a 1957 olds 88 4 door hardtop.
Solid 22" mercury at idle,
RPM @ 850-860 at idle, 450 in gear,
4 barrel Rochester (1957 vintage) which I rebuilt with all new gaskets etc...
F/A screws out @ 3 turns
Timing set at 5 degrees with vac. advance unplugged.
With it plugged in runs @ 20-25 degrees.

Currently there are 2 ports in the throttle plate. The front one goes to the dist. and the rear one goes to the throttle dashpot (anti stall doohickey). It starts before it makes even 1/2 a revoloution. which is great. the idle quality however... The RPM surges back and forth and in gear moves alright. Big time hesitation while in gear and above idle. In park you can rev it up slow or fast all day long. In gear tho it seems real sluggish. the engine doesn't sound great either. it seems to sound like a diesel. Not 'dieseling' just that odd sound that a diesel makes.
Put my head by the exhaust pipe and seems to have a random soft popping, not loud backfires. Also still running real rich.
Right now it drives better on the road with the vac. advance disconnected. Not great, just better.

Any ideas?