I have this problem since I bought car. I set fueling at full throttle at about 12:1 , idle mixure is ok, I check belt, timing is ok, ignition timing is set to about 12 degrees, changed sparks, cables, boost hoses. And again, when I suddenly push throttle, for example driving at 2000 rpm in 2nd gear,and flor it, engine wont pulling so good, expecially when engine is hot. Goes good, and at about 3000 rpm starts do like I pull handbrake.like I give it to much gas, and engine start to choking.but sparks are coloured like rust or chocholate. I dont know what to see.next on my list is see cam. I dont have other ideas.