Looking a the picture in Frito's post it looks as if the base of the carbs. might be above the hood level. That may be the reason,or there is just not enough space when they are sealed to the hood. If I were you I would not go with the factory style hood scoops. They look the best on the cars,but they may not be the best. I put a cowl hood on my 67 R/T and pick up another .05-.06 over the factory Hemi style scoop that picked up about .06 in the 1/8. In all I picked up a little over a .10 with the proper hood scoop in the 1/8 mile.