They say a "smokey" truck will dirty the engine oil faster. I think? To get more smoke you need to turn some screws on the pump. Yours is a 1st gen. right? Do a search on turning up your fuel. To get more smoke you gotta have more fuel, or at least get the fuel there faster. If you just want smoke, but no more fuel, you probably want to turn the starwheel clockwise. To get to it, remove the 4 screws on top of the pump, along with the cap. Then pull the diaphram out(thats the plunger with the rubber piece around it) The starwheel is that thing that looks like a gear.