I have no smog control devices on my truck! (Lucky to be in Korea I suppose!) No EGR, canisters, etc... The only line I have hooked up is the vaccum line from the distributor and one for the choke pull off. Where does the line go from the distributor? Passenger side or drivers side front port? I have set the timming, disconnected and plugged the line of course, and notice no difference in the timming mark. Seems to run the same. Connecting the line to either side of the carb also yields no difference. Is this "normal?" I read about full vacuum or manifold vacuum, yet again, I notice no difference. Both of the ports on this Q-jet seem to be aligned with each other at each corner of the carb. I'll pull the hose and connect it back and forth trying to find some difference in driving and agin, notice nothing. Opinions, suggestions? Happy Holidays all from Korea! You are all lucky to be with your families! It's FREEZING over here! Below zero!