On Sat, 23 May 2015 18:49:13 -0400, Keyser Söze
wrote:

Whatever is being measured, it isn't likely that car is delivering 46
mph at 90 mph. Period.

===

Ignoring your drunken typo, let's do the math. If a car is getting
46 miles per gallon at 90 mph, that means it is burning 2 gallons per
hour. 2 gph with a gasoline engine implies about 20 horsepower (10 hp
for every 1 gph - good rule of thumb). It seems unlikely that even a
slinky car like a 'vette could do a sustained 90 mph with only 20
horsepower. More likely it was either a transient reading or some
sort of glitch in the instrumentation.