A lap of Sepang with Alex Wurz
The circuit is a great challenge so it's a pretty full-on weekend for the teams.
You arrive at the first corner in seventh gear, at about 310kph (192mph). There is a lot of grip from the asphalt, so you can brake really late before turning in third gear. The rear gets a bit light at this point.
You then have the left hander at turn two, which is the slowest corner on the circuit. It's first or second gear and it has a camber change in the middle, so it's quite difficult to find the right differential set-up for it.
Next comes a long right-hander, which is easy-flat even in the wet, and then you're braking for the right-hander at turn four. The braking area is really bumpy, which makes it a bit tricky, and then comes a really nice part of the circuit.
You enter turns five and six in fifth gear, at 230kph (143mph), and the entry to turn five is almost flat so you really have to squeeze the throttle and make sure you have a very late apex. There's an immediate change of direction and at this point we pull about 4.5g. You might touch the brakes to stabilize the car into turn six, which is incredibly bumpy and the rear gets very light. Don't forget that we are still at 220-230kph (137-143mph), with not much run-off, and I really enjoy it!
Then comes a double right-hander, which is easy to get wrong if you overdrive and it leads to a hairpin. It's first or second gear and it's very important to have a good exit because that gives you pure lap time.
Then we go to another flowing section, which leads to the penultimate corner. It's very difficult here because you enter it very fast and the rear gets very light. You have to brake down to second gear while turning and the car is oversteering the whole time. It's very easy to overdo it.
The last corner is another hairpin and we again brake very late, from 300kph (186mph), down to second gear.
This 15-turn track contains a variety of corners, from a tight second gear hairpin leading on to the pit straight to two high-speed sweeping corners at turns five and six and a fast double-apex right hander. With such tricky combinations of corners, braking stability is key, although with understeer predominating in the long slower corners, getting a good balance can be difficult.
An evening race in Sepang is going to be about one thing, thunderstorms. As convective clouds build over the circuit during the day, the cooling conditions of the late afternoon trigger heavy downpours. For the qualifying and race sessions this could really mix things up.
The larger difference in grip between the slicks and wets in 2009 could mean a test for the drivers. The Sepang circuit is physically demanding because of heat and lateral forces. The track surface is now quite old and with the substrate not fully compacted bumps have increased over time. For the engineers, the set-up here is one of the toughest of the season and with the soft tire will be even more tricky.