Estoril is a good circuit and very challenging. Physically it's a tough track; it's bumpy, so it's hard on the car. You still need a good engine because of the straights, and it's reasonably high downforce as well. Overall it's quite a good track, and Estoril is a nice place.
There is a series of bumps on the entrance to the first corner, so it's quite difficult to set the car up, because it bottoms out. You turn in in fifth or fourth gear, depending on the balance of the chassis. It's a quick corner, about 3G. You accelerate all the way through to Turn 2, which is extremely quick. It's fifth gear, and there's no run-off area. You're really on the limit of adhesion with the car, and you've got to have it well balanced. It's easy to run straight off the kerb into the barrier.
You come down into the next righthander, which is very slippery normally. It's very easy to run straight off into the gravel. It's second or third gear, depending on gearing. You accelerate uphill, normally struggling with oversteer at that point.
Uphill you shift into fourth gear, and then come back down to second gear. That lefthander is very bumpy, and it's difficult to get the car balanced there because of the bumps. Then it's hard out of the hairpin and onto the back straight. The kink is not much of a corner really - it's quite easy to get through there flat out. You carry the speed through in top gear, coming down to the third gear, double apex lefthander. It's a pretty twitchy corner because you're coming in at a high approach speed. It's very easy to overcook it and go too quickly into the corner. And also it's difficult to get the front end into the corner. And also it's difficult to get the front end into the corner and make it stay there, because it's easy to turn in and then understeer out onto the marbles and use too much track too early.
You hit the second apex, accelerate hard again, exit onto the kerbing on the right, again picking up a number of bumps. You go back up into fifth gear, and then into a fairly tricky second gear corner again. It's important to get the car stable for the entry, and it's cambered as well, so you've got to get into that camber and use it to your advantage. If you get the other side of it, it slows you all the way round.
Traction is a bit of a problem there as well. A quick squirt up the hill, fourth, and then you turn into the new chicane, normally just dropping the right hand front wheel over the grass to cut the corner. Then you are hard onto the brakes ready for the first gear lefthander. It's easy to go in too quick. It's a bit frustrating, because the corner that was there before was quite exciting and challenging, although the run-off area was very poor. The new corner breaks your rhythm, and it's hard on the transmission, brakes and engine. You struggle your way through there, accelerate hard, and come up to a third gear lefthander. It's always an understeer corner, and you use all the track.
Then you build up for the last righthander onto the pit straight. It's fourth, and then you change to fifth, and you try and get yourself flat in fifth gear on the exit. Again you're pulling up to 4G, and you're problably in that corner at that high G for something like seven or eight seconds. It's probably one of the most important corners, because it determines your speed all the way down the pit straight. But you can use the kerbs too much, or go too wide and pick up the marbles on the outside.
The good passing places are at the end if the pit straight, possibly going into Turn 3 if you're quick enough through Turn 2, and possibly on the back straight as well.