I spend a lot of time on the theory side of things, and I've got one particularly good tip to share:
To find the fastest line around a track:
1) find the best, overhead-view, map of the track available. It's important that the map portray the width of the racing surface, not just a line. For our purposes, we can ignore elevation change to keep this exercise from requiring professional CAD software.
2) start drawing a straight-line, using a ruler/straight-edge, backwards from the outside edge of the finish line. Make this line as long as possible until it exits the track, probably somewhere close to the middle of the outside edge of the pavement on the last corner before the start/finish straight. The longest line possible will be tangent to the inside of the pavement on the last corner, and this tangent point will show you the ideal late apex (see notes below re: exit speed)
3) from the point at which the first line exits the track, start another straight line, making it as long as possible until it also exits the track.
4) rinse and repeat all the way round the circuit.
This exercise helps break the habit we all have of apexing each corner individually at the approximate mid point. It also helps to emphasize the critical importance of "corner exit speed" versus "average corner speed." There's a solid reason behind the old adage: 'Slow in, Fast out!' ->It's because exit speed results in increased speeds all the way down the straight sections that follow combination turns, allowing you to cover more ground faster than the same car with a higher average corner speed.
Because of, and related to, the relationship of higher exit speeds to faster lap times, the fastest line around the track is the one that allows you to maintain wide open throttle for the longest period of time, and is also the one that allows for the highest exit speeds from combination corners that lead into straight sections. Drawing all these lines backwards around the track shows you, in a very simple way, the earliest point at which any car can execute wide open throttle (assuming 0 slip angle), theoretically resulting in the highest possible speeds on corner exit and ...
faster lap times!
