Check the "static' timing by setting the idle RPM's to specs (about 550 RPM's) then disconnect the vacuum hose from the dizzy.I believe it would be "total timing"!?
Disconnect and plug it to check the initial advance (initial advance is the timing at idle). But the initial advance is not all of it- you really need to know what the total timing is (total timing = initial plus mechanical)- or else the engine can be damaged or have poor performance from detonation or insufficient advance at higher RPM.I'm interested in just "checking" my timing mark on my 64 Chevy smallblock, do I still need to plug the distributor vacuum hose? I don't plan on adjusting at this time!