Dart 340 twin hood scoops
The later twin snorkel common scoop is more effective. But really only because 1% gain is better than zero percent gain.
As mentioned, air touching the hood is basically stationary, and the further you get from the hood surface, the 'faster' air is moving (in other words, vehicle speed).
Cold fresh air is better, but with no ducting to the air cleaner and no speed, the twin scoops are, as mentioned, heat release. I wouldn't be surprised if air flows OUT of them at freeway speed.
The later twin snorkel common scoop is more effective. But really only because 1% gain is better than zero percent gain.
As mentioned, air touching the hood is basically stationary, and the further you get from the hood surface, the 'faster' air is moving (in other words, vehicle speed).
Cold fresh air is better, but with no ducting to the air cleaner and no speed, the twin scoops are, as mentioned, heat release. I wouldn't be surprised if air flows OUT of them at freeway speed.