can the pipe that the banjo fits to not be made shorter so its not up so high or swivel the banjo around a bit if space allows?
does the banjo bolt have a washer between the hex part and the banjo and between the banjo and turbo as im pretty sure that can interfere with flow as the hole doesnt line up like it should?
also should that hose to the top of the rocker cover have a jubilee clip on it?
sorry if none of this helps but i thought id say somthing even if it doesnt
help as im always having a look in this thread just never commented love the car hope its a simple fix for you and you can enjoy it a little more soon