I see from reading other posts on here that the quadrajets are supposded to be pretty decent carbs for wheelin'... Ummmm... Mine, if I am parked on a steep uphill grade will start loading up. It will get to the point of dying in about a minute. This has not happened on the street, but most roads aren't that steep. The truck just passed emissions the day before I bought it. The owner said he leaned it out and retarded the timing to get it through. I think he richened it up to much afterwards. The tail pipes were black and sooty, so I adjusted the mixture screws by ear. One in particular was pretty rich. The carb idles great on the level, has no flat spots under acceleration, and the secondaries seem to open fine... Any suggestions?