You said that you had to raise the intake so the carb would fit!
It sounds to me to be an air problem.
You have to much air coming in around the intake or carb.
I bet it's the spacer you put in-between the original manifold and head.
Have some one spray starting fluid around the intake wile you start it if it starts then look for the leek.
Buy the way I have the same carb and I made a intake out of the original Puch that swung the carb out to the side.