High Speed driving

[Vikram Mittal <VMITTAL@ecs.umass.edu>]

While driving my 1990 Audi 100 (5 cyl) for some time on the highway 
I noticed something quite interesting.

Initially while I was sometimes going just over 75 mph the Audi seemed
to be quite slow and required considerable pedal effort and I had to press
the accelerator quite a lot. However, after driving at about 75 mph
for a couple of mins, it seemed to now do 80 + mph quite easily.
In fact, even 90 mph did not require the accelerator to be depressed
to much.

I have observed this several times since. Is this my imagination ?

Also, the accelerator pedal *definately* seems to have two modes.
After pressing it some, it becomes decidedly harder, and when I press
it beyond this wall, the engine pulls quite strongly too. Any 
comments ?

Vikram.