[robertwb70]

Two things come to mind, since you have a more restrictive inlet now you can either reduce some of the new restriction or improve the airflow out of the engine compartment like Neil suggested, but I don't think you want to cut holes in the car so we'll skip that part.

Those vents actually have 2 sets of louvers at 90 degrees to each other, the movable ones and the fixed ones, it looks like the fixed ones block about 50% of the opening when the others are fully open so I'd reduce that by removing some of the fixed obstructions. Might think about removing them in blocks of 2 or more or maybe every other one since they are probably needed to support the other parts but certainly not all of them are necessary.

(I was thinking about the original vents, not the current setup)