so.. i make two of those somewhere on the rear of the canopy by making the cut in the fibreglass, push it down using the narrow end as a hinge and add a couple of ply sides, any air that enters the engine bay via the carb access hole, nose ring and around the head flows to the cooler canopy and gets sucked out these holes right? the rectangle exit hole is my area to be considered and compaired to the entry areas.. think i've got this.
last question, what shape should the carb hole be to stop air being sucked out as it passes, i dont want to ram air in there by adding a scoop, should i put a small lip on the LE of the hole to create a dead air area that the engine can breath from?