Cant Keep Timing Right

[cvan1971man]

Got a 1978 FJ40. We have electronic ignition in it. It seems like we get the timing, idle and air fuel mixture dialed (Holley 2bbl) in and then a few days later and 40 miles on it, it is out again.

Any ideas as to what the cause could be?

 

[JohnnyC]

What distributor do you have? Centrifugal weights might be rusty and/or sticking

Timing with vac advance disconnected right?