IMO, the minimum is 2-1/2 inches but I’d also call that to close for best operation. 3 inches or better is what I hope to get under the hood. And that is the problem, hood clearance. Here is an example of my issue on the wife’s car.
The car: A ‘67 Cuda w/a 360, RPM intake, AFB & a thick Edelbrock carb gasket which IMO is key for a cool running carb. I run the Mancini drop base filter bottom just so I can have some filter area since it’s cramped in there. The filter is a WIX 42044 to fit the black ribbed MP air cleaner.
From the top of the air horn to the bottom of the lid is a tiny 1 inch. This is choking the breathing I’m sure but I can not go higher since the wing nut pushes into the hood insulation. A hole in the hood is NOT an option nor is another hood.
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