As for the area above the intake (I call the intake "head" clearance) there is very little room on the coupe. The front carb is especially tight, about 1.75" The rear could be about 3" but I decided it would be best to be symmetrical.
We made custom "low" air horns 0.450" tall (+.250" for the baseplate). It is my belief, however, that air horn height is only useful for tuning intake runner length. I see little to no evidence of power or flow increase beyond a nice radius'ed inlet.
