Haven't they proven "ram" air to be a marketing ploy? Most of the power gains in automotive uses was from the colder air from outside the engine compartment. At normal automotive speeds it doesn't work as a "Ram." I remember reading that the point where it begins to gain effect is in the 130 mph range. Buggies will never see enough speed for ram air to work. But some good cold fresh air will and it will add some style points.
http://www.paladinmicro.com/documents/RamAirMyth.pdf
There are many other similar sites to the link if anyone wants to do some digging.