Aerodynamics
Edwards
I've recently had several discussions with customers and friends that have said "a kart that goes 60 mph is not affected by air flow." In response, I'd like to quote former NASCAR driver and current announcer Darrell Waltrip, "anything that moves is affected by aerodynamics."
A kart is probably one of the most aerodynamically challenged vehicles in the world, but like with any vehicle, you have to balance a kart's body design with practical functionality. Yes, we could design and build an exotic design, but cost and practicality will prevent it from ever being used. Does PRC in fact have the "perfect kart body?" Definitely not.
Putting design aside, let's turn your attention to adjusting what you already have. It's obvious that the most important component in the aerodynamic package is the nose itself. Different nose designs will produce more or less down force, but there is another factor that greatly affects the efficiently of any nose and that is how it is mounted.
One of my biggest pet peeves is to see a kart with the nose mounted 3" off of the ground, and pointed up in the front. Then the driver complains, "this thing pushes like a bulldozer..." I guess so; you're forcing all of the air under the kart, instead of over it.
If you've watched any NASCAR races recently, you may have noticed that they place a lot of emphasis on car travel and sucking the car down to the track. This is done to increase down force by forcing more air over the car instead of under. We don't have suspension to provide travel, but we still want the body as close to the ground as possible, without it hitting or rubbing.
You cannot race a kart with the nose 1/4" off of the ground and it be functional. We have found that for most dirt tracks you can run an average of 7/8" ground clearance. Usually, we set ours so that the left side has 3/4" and the right side has 1" clearance on a level surface. This allows the body to become pretty level when the kart is loaded in the corners.
Another advantageous aerodynamic accessory is the rear floor pan. Our rear floor pans allow the air that does get under the kart to flow evenly, instead of being caught on various parts of the chassis. In addition, the rear deflectors helps to remove the air from underneath the chassis, thus creating more down-force. And as you know, more down-force equals more speed!
From PRC connections
