Calculating Frontal Area

[saltfever]

The most accurate methods are John’s (reply no. 3) and Panic’s (reply no. 9). They are both quite easy. Panic’s method is the best if you do not have a CAD program. Thank you both for posting.

Something super easy, fast, and almost as accurate, follows. However, note Panic’s reservations above.

Park the front of your vehicle in the garage doorway. You now have a perfect physical measurement.
(1)Take photo from as far away as possible.
(2) Measure height and width of the doorway.
(3) Using an architect’s or engineers scale transfer those precise dimensions from the doorway to the photo and draw a grid pattern.

A small discrepancy in area may not be a big deal. Your Cd probably will be less precise than the area you calculate. Cd numbers should be suspect unless they have been calculated by a real coast-down test or a wind tunnel. A small .01 or .02 error in Cd may result in greater drag error than your physical measurement of area. Since HP increases as the 3rd power of speed, I am not minimizing precision as a goal. However, traction on the salt varies by the hour and it may become a greater variable than absolute precision in calculating CdA.