Consistency is key. I don't really practice much anymore, because I know all the tracks in the game. Mostly it's the cars that I need practice with. But I know how the Toyota behaves, so I don't have many issues with it. I know the tire wear, and I know the grip levels when the tires go off from lap to lap. If you can get that down, you shouldn't have a problem. So lets say you start your stint at Indy and on the first flying lap you can do a 1:33.xxx, you may be able to hold that for 3 laps, then on the 4th lap you may be a second slower so lap 5 (considering pace lap) you turn a high 1:34, then maybe the same for lap 6. Then the tires are going to go off more so another second is lost on lap 7 and 8 (maybe more). If you end up dropping to where you're lap times are 4 seconds off the pace; it's time to pit. So lap 9 you're starting a new stint- there's no reason to refuel, so that should save some time in the pits as well ad make your car a little faster. So after your out lap (lap 9), on lap 10 you can shoot for a 1:32, or a low 1:33, then keep the consistency like the last stint. That's how I try to manage it.