Reply to "Ground Effects"

Back on topic. Inspired by Goram Malberg's approach to measuring ground effects, I looked up the manometer in an old chemistry book. Now, I'll explain how to make a simple, inexpensive manometer to test downforce created by ground effects.

Take a clear plasic hose, any diameter, and seal up one end with a plug. pour water into it and make a "U", then flip the dry end of the monometer over and back down, letting the water spill out. Mount the manometer on a piece of wood and fix it stationary on the inside of the Pantera, visible while driving. Take the other end of manometer tube, the dry part, and run it to the underside of the Pantera where the measurement of vacuum is to be taken, or measured. When the vacuum measurement is taken while driving, the "inches of water" will be the length of air created at the end of the manometer which is sealed, or the distance the other side of the 'water column' goes up with the application of vacuum. The manometer can also measure "inches of water" for positive air pressure, and the column of water will just go the other direction. Water is used instead of mercury because it is safer, free, and readily available. It just travels greater distances up or down the manometer. The "inches of water" is a force of vacuum or air pressure which can be translated into pounds of downforce, depending on the surface area of the ground effects device: rear wing, underbody panel, etc.

I e-mailed Professor Goram Malmberg and asked if he'd like to contribute to this topic and to please keep his website updated with the latest information he has to share. Any other contributions are also welcome, and invited.