Up And Running With Issues

[Richie-Van-GTi 70 2 Cars]

Finally got my car started, it will idle around 1000 rpm but as the cam needs breaking in I have it idling around 1800 rpm, it has a small misfire at random and only occasionaly, also it seems to be very very rich even though lambda should be at 14.7 its reading at 10.6 , guessing this is the misfire. I noticed however my bodge job on the downpipe hasnt sealed against the manifold so unsure if this is the cause of the over fueling? If I try to open the throttle up she just borks like crazy, is this down to fueling?