well that's your problem your distributor is out of wack set #1 cylinder to top dead center and pull the distributor then put it back in so that the rotor points to #1 cylinder and set your timing from there i usually go for 8-10 degrees on a stock motor
The vacuum canister can advance 24 degrees beyond initial timing.
8 to 10 degrees BTDC. / before top dead center. 10 May be to much. If it pings and rattles are is hard to start when HOT then slow the timing up alittle.
around 6-8 degrees with the vacuum advance blocked off. electronic ignition has no vacuum advance! How does one blank off the electronic advance???
6 to 8 degrees BTDC / Before top dead center. with vacuum advance pluged.
That engine does not have a vacuum advance.
SBC timing should be set at about 6-8 degrees advance with the vacuum disconnected at idle, about 600-800 rpm
84 has a vacuum advance 89 has an electronic advance Thats the only diff.
Spark plug gap is .035, point gap is .017 to .019 or 30 degrees dwell. Timing with the vacuum advance disconnected and plugged is 4 degrees. If you have a timing light with a dial for total advance then it is 35 degrees at 2,000 RPM.
10 degrees advance
You can purchase an aftermarket adjustable vacuum advance canister from most any auto parts store and follow the instructions for installation and adjustment.
California emmissions full,49 states part
There is no set timing for this specification. If you are using a mechanical advance distributor rather than a computer you will initially target 35 degrees total advance over 2500 rpm with an idle setting of 10 degrees with out vacuum advance. From there experimentation to determine most effective setting for your engine.