I have a 66 Mustang and I am installing a Shelby hood scoop on my hood. I have a Oval Cobra air cleaner assm. If I cut a hole in the hood for it to be funtional, should I cut a round hole or a oval hole to match my air cleaner?
The theory, with the biggest hole possible idea, is to flow as much air through the engine bay over the AC and engine and out under the car to maximise cool air charge to AC.
This MAY hinder airflow through the radiator though.
Without a plenum under the hood enclosing your carb, at highway speed the air pressure under the hood is greater than scoop intake pressure. Drive the car in the rain & watch the raindrops being blown out of the scoop. It doesnt matter how big a hole you cut in the hood.
I thought that the scoop might work backwards at speed, because of the location. It'd be best to have a reverse scoop in the middle of the hood (an extractor) or cowl induction at the, well, at the cowl.
Without a plenum under the hood enclosing your carb, at highway speed the air pressure under the hood is greater than scoop intake pressure. Drive the car in the rain & watch the raindrops being blown out of the scoop. It doesnt matter how big a hole you cut in the hood.
I did not need to hear that. I would have preferred to remain ignorant and labor under the delusion that I was actually increasing air flow to my carb with a hole under my Mach 1 scoop BUT NO, somebody had to go and be all Dr. Science and inform me that the hole in my hood is doing more harm than good. Thanks a lot.
if you wanted a true functional ram-air scoop, i would look at a 67, the 65/66 scoop sits too far back, and too low it be in the path of pressurized fresh air.
however, by sealing off the scoop to under hood pressure, the scoop will still draw cooler air from outside the engine compartment, just wont be pressurized... like a "ram-air" set up
i actually sliced and diced my "real style" gt350 hood(metal understructure) to raise the scoop opening about 1" so the opening didnt look "small".
mine has a closed cell foam "pan" that seals it too the bottom of the hood, the air cleaner is inside the pan. i seriously doubt it made any gains at all sealing it off, but it sure does "look" functional when ya pop the hood..... the pan also hides all the NO2 components nicely.