I have a mildly rebuilt 440 with a plain ol Holley 750 and was wondering what the best timing setting would be and basically how to do it.
I have the chrome Moper Performance timing chain cover and the MP timing tape on the harm. balancer. I have a 70's Mopar stock elec. distributor. I dont race my car and dont take it out on the highway. It actually idles pretty good and accelerates fine; but there is some weird 'missing' while cruising at around 40mph. Not real bad, but not acceptable. I was told to try disconnecting the advance hose to see if it goes away. I was hoping someone here could shed some light on the subject.

use a vac gauge along with the timing light

set timeing for highest vac reading

adjust idle air screws on carb to highest vac reading

back and forth till you get the bestest highest reading with vac can on dist unhooked

adjust curb idle on carb and repeat steps to fine tune it

old racer trick is to set cub idle,use vac gauge and turn dist to get highest vac reading...back off one full number

i.e....if your highest is 14..back off to 13 and test drive it,,adjust again if needed

rpms should only drop a little when going from N to D at an idle and not jeck the car as it goes in gear

results will vary

find what your engine likes and use those numbers,,they may differ slightly than any books

what RPM are you at when at 40 MPH? then check your timing (vac adv connected, duplicating the actual condition) at that RPM & post it. I'm assuming steady high vacuum (low load) at the 40 MPH prob point? disconnect the vac adv & (re)try it which'll shift the phasing CCW & post if this helps (or hurts) the missing.