So I think that using the pitot tube as a static reference is a much better approach than using the sealed vessel as the reference. Thanks again to cr45 for the excellent suggestion.
I have redone all of the Honda's measurements.
Note that the basic pattern remains the same as with the previous measurements - for example, no negative measurements became positive or anything like that! However, I think with the pitot tube static reference, the absolute figures are much more accurate.
I also did an additional measurement in the middle of the roof because I suspected lots of lift might be being generated here because of the roof curvature (and I was right).
Test:
- Pitot tube static reference located 2.2 metres above ground
- Magnehelic 0-3 inch of water gauge
- Custom measuring puck (easy to make yourself)
- 11 degrees C, fine and clear
- Light winds
- 80 km/h test speed
- Average of two measurements in different directions
- Pascals rounded to 5
Note: the Insight runs full front and rear undertrays, with the rear undertray incorporating a 10 degree diffuser.
