I suspect it was the same infamous GASAX, lead aircraft of the Jacobite Air Force and based at Netherly at that time.
Consumption wise I used to average 7.5 to 8 gallons per hours - with about 0.25 to 0.5 pt of oil - once all the rings had been sorted. That would give 90kts
I remember being amazed reading the Pilots Manual cover to cover and having explored the time to height tables at all sorts of speeds and landings at many altitudes, being unable to find even a single mention of fuel consumption....