reminds me of pneumatic damper controls used in HVAC. pretty sweet.

 

Seems like this could be done with engine vacuum. The old Chevelle SS had a hood flapper that would open when at W.O.T. (zero vacuum).

I think the challenge would be to find a vacuum motor strong enough to hold it open/closed.

The QTP system ( http://quicktimeperformance.com/Controller/index.php )
with an electronic controller. It also has an input to ground the switch and close the valve.

Expensive, but will work.