The biggest difference is obviously the feedback. Very subtle judders of the
steering wheel and brake pedal when approaching the limit of grip can never
be accurately reproduced in a sim, but everybody says that so I will move
on.
The second biggest fact in my opinion is that race cars (all cars, in fact)
seem 'keyed in' to the road. It actually takes a surprising amount of effort
to spin a race car if you are driving it properly - you get a lot of warning
signs from the wheels before anything starts to give. In GPL this feeling is
non-existant - there almost seems to be a layer between the tyres and the
road slipping against them both. You can get realistic laptimes and such
from GPL, but in a real race car you can drive at 90% fairly easily and
consistently with no major 'moments', but in GPL driving anywhere above 70%
is constantly twitchy and unstable. This all depends on the race car you
drive, of course, and I am bound to get a whole bunch of people mailing me
telling me how twitchy '67 GP cars were. You can look at the GPL intro video
to get a perfect example of what I mean. There is a shot of a car coming off
the in-built banking at the Karussel out at the 'Ring. I can't remember
which car, but just look at how the car is reacting to the balance change
and regaining grip. Now try to do that in GPL...
GPL is by far the best, but there is still a long way to go.
--
Nick
"The overriding purpose of software is
to be useful, rather than correct."
John Carmack, id Software