I have now done a two-way run on my Insight with 14 pressure taps plus the pitot tube static pressure reference. It's a lot of work to fit all the taps and ensure each is connected to the right port! All taps except #14 just offset from centerline.
Tap 1 - Front undertray
Tap 2 - Stagnation (number plate)
Tap 3 - Leading edge of bonnet
Tap 4 - Trailing edge of bonnet
Tap 5 - Centre windscreen
Tap 6 - Leading edge of roof
Tap 7 - Middle of roof
Tap 8 - Trailing edge of roof
Tap 9 - Centre rear glass
Tap 10 - Lower third rear glass
Tap 11 - Centre of ducktail spoiler
Tap 12 - Wake (centre of bumper)
Tap 13 - Rear diffuser
Tap 14 - Centre side undertray
Tap 15 - Cabin (not connected)
Tap 16 - Static port of pitot tube (ie ref pressure)
I did a screen grab of each run:
Going north:
Going south:
Note the variation in the unfiltered signals.
Three pressures varied greatly on the different runs - trailing edge of bonnet (#4), centre of the windscreen (#5) and centre of ducktail spoiler (#11). I assume there was plenty of yaw airflow - day is quite gusty (up to 30 km/h).
Averaged pressures:
These largely agree with what I have measured previously - while there are some variations in values, the pattern is as before.
But I urgently need averaged values rather than the 'snapshot value' at the time I do the screen grab. I can log a run and then average in Excel, but I'd much rather the software had selectable smoothing. I might try logging and averaging tomorrow - logging was a bit fiddly when I experimented on my desktop PC, so it might be hard in a moving car!