Even though mine is not supercharged, I plan on doing the devil-horns before too long.

My current setup puts the TVT intake tubes *just* behind the core support (maybe 1/2"), but with no straight shot to the outside air. Once the car gets moving, there is more than enough cool air coming in and the gap becomes moot.

Having said all of that, I plan on installing them simply to complete the job. At a standstill, there is potential for the intake tubes I'm using to suck in a wisp or two of hot air from the radiator area... DH's would eliminate that and prodive an uninhibited path to cool clean air.

As for dyno #'s, I can't imagine them giving you much of an increase when you're strapped to the rollers with no REAL air ramming into the front.

At 120mph, however, I'm sure the funneling effect would realize significant gains.