First saw the hood louvers on a 2010 Roush prototype. They had the louvers punched in the hood, not a separate panel and further back. Cost too much for production so they were dropped. MM & FF did a test on a 4 eye Stang and gained almost 20 hp with a heat extractor hood - dropped under hood temp that much to make a difference.
2015 Stage 3 Roush
'66' Ranchero w/almost done 302 T-5 swap
2000 4x4 Ranger
2003 4x2 Ranger
'69' Fairlane Cobra, 428 4-speed waiting for work