I think the design is shit. Clearly constrained by the design specs of the stock cowl. One pipe sucks in competition with the other, reducing effective surface area.
I'd do away with the scoop, heat shield etc and run them as far apart as possible. If you wanted to be really sneaky modify an M3 bonnet to fit a meshed breather around the bump and draw fresh air in from the top - maybe an intake like the wrx's have...