Bill,

My concern is that if the instrumentation is really measuring inches of Hg and has an offset, the sensitivity may be such that a significant difference in pressure may not show up in your data.  If you are seeing an increase in pressure as the airspeed increases, then just the units of the measurement are probably incorrect, but your conclusions would be valid.

Steve

That is a good point, Steve, but the real info in the data was the fact that there was no pressure difference between the inlet and outlet side of the radiator.  After the pressure built in the cowl to whatever point, the pressure then stayed the same all the way to the inlet of the nostril.  No more could come in because there was no place for it to go.

Bill B