hey i just put a new distributor in a 1980 4x4 p/u when i got it ,it was differant than the one i took out.it had two ports on the vac. advance,and mine had one .i called rock auto and they put me on the phone with the guys who remanufacture them and he said itd work with my truck if i use the top port,instead of the other one becasue it was a vacc. retard somethin or other?do i need to plug that off or what??

 

no you dont .. just use the top port
or simply remove your old vac dia. from your old dizzy and replace it on the new one


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