For testing, I always use Midfield for the following reasons:
I know it very well
Sounds stupid, but is a very basic rule. If you don't know a track well, you can't make consistent laptimes on it, which means that you're rather having luck than really testing a car. I already used Midfield for testing in GT3, and it is the track I've made the biggest number of laps on by far.
It is farily universal
Let me talk you through it, and I'll tell you what you can find out where. We're talking about the normal, and not the reverse direction by the way.
- the first corner shows you how the car behaves under heavy braking and steering (Will it under- or oversteer? Will the front wheels lock up? Are the brakes weak or strong? Is the brake balance okay?)
- the second corner shows you how the car behaves during accelerating through a whole corner (Will the front push wide, or will it stay level? Does the car accelerate slowly or quickly?)
- then you'll find a high-speed chicane, which shows you how much high speed grip, -stability and downforce you have. In a car with good grip, you can go full speed, while you'll have to lift or even brake in a car with bad grip. Pay attention to the speed you're doing though! You can also test liftoff-oversteer at high stability here (does the car get instable at high speeds when cornering? Is there enough downforce?)
- The following double right shows you if the car is susceptible for understeer if weight is taken off the front (which happens in the second part of this double-right)
- the sharp, long left shows you how the car behaves if you hit the curbs (Elises for example tend to become instable easily here) and how early you can step on the gas before running wide (does the car understeer with no power applied? does it understeer at half or full power?)
- in the downhill, you gather a lot of speed. Braking for the final sharp left into the tunnel, you can test stability under weight transfer to one side and heavy braking (some cars tend to spin out here regularly).
- in the sharp left, you can test how quickly the car responds to various manoeuvres applied in a short period of time (braking hard trying to keep the car stable, getting off the brakes and turning left hard at the same time, hitting the accelerator). Additionally, you can test the grip out of sharp corners (Powerful RWDs tend to spin the wheels here, FWDs can push wide easily and also spin their tires)
- The uphill final chicane shows you if the car has enough grunt to maintain acceleration uphill. Some of the weaker cars completely stop accelerating here
So, that's why I use Midfield for testing.
Regards
the Interceptor