does any body know what to set the timing at.i have a 1963 chev impala 283 2 bbl automatic trans i put in a 1979 HEI.distributor.do i stay with factory settings,or should i just do it by ear!and leave it at that.and do i need to go to a hotter plug?any help appreciated
The HEI will have an entirely different advance curve and you’ll have to probably do some experimentation to get it where you want it.
Normally these set at about 4 degrees BTDC with ported vacuum disconnected.
If it were mine I would try 6 degrees BTDC on a set of new plugs. Stay with the called for plugs until the experiments are finished.
After putting about 50 miles or so on it, pull the plugs out and examine them. If they’re dark, try advancing the timing a couple of degrees. If they’re whitish in color, then retard it back to 4 BTDC.
The plugs should be cleaned and reinstalled, followed by repeating the process. Yes, it can be a pain but the alternative is a bigger pain - a damaged engine.
I’m not a big fan of using an ear for ignition timing. Considering the worthless grades of gasoline out there it would be very easy to have too much advance in the timing and this could cause engine damage.
Especially so since you probably do not know what the total timing advance is going to be with the HEI on that particular engine.
Hope that helps anyway.