Wow.. that's 5 right angle bends and some pretty crinkled piping... there's got to be gains to be had with some pretty simple smoothing of the routing.
Would it be possible to re-locate the MAF sensor above the throttle body.. turning it horizontal and mounting something like an ITG Maxogen housing directly above it with the Maxogen housing intake pointing forward possibly to a NACA duct in the RHS of the bonnet?
http://www.itgairfilters.com/airboxes.asp?section=maxogenairboxesThere is a 1.8 Focus installation that might be able to be modified slightly to suit.. or at least ITG will have experience of the engine charactereistics and therefore only packaging will be the complication??