I wouldn’t want the IC horizontal between the the airdam and the hole in the grille. You’ll have opposing pressure on both sides of the IC which will cut the flow through the IC down. I’d say you’d have to do the horizontal mount one of two ways:
- Air dam and grill closed so air goes through ic then radiator. This should work ok if the engine doesn’t overheat with the ic in front of the rad in the vertical position.
or
- Leave the grill open and have an air dam or splitter IN FRONT OF the ic, i.e. near the leading edge of the grill. This way the air will come in through the opening in the grille and get sucked through the rad by the fan and [in theory] get pulled downward through the IC by the low pressure area created in the wake of the air dam.
As stated previously if you aren’t overheating in the current config I would leave it.