Before the start of the weekend, the main question was the tyres. In what way could Michelin react to the accusations from Brawn and Bridgestone, and did they have enough time to produce a performant new front tyre? Whether it was because of the tyres, or just pure performance of the car, Michael Schumacher was able to win from pole. The Ferrari team was clearly very happy and relieved with the victory, underlined with a third place of Rubens Barrichello. Montoya had put too much downforce on his rear wing, and had an incorrect tyre pressure at the beginning of the race, which caused him problems during his first stint. An improved McLaren couldn't change a thing about that, and afterwards, it became clear that Kimi's chances to become the youngest champion ever are rapidly fading away.
McLaren gets the last from their MP4/17D
In an attempt to keep Kimi in a good position to win the championship, the MP4/17D has undergone a revision, in which the sidepods now look like the MP4/18. As the current car is running to its end of its potential, a serious step was needed to even keep it holding on with the topteams, being Williams and Ferrari at the moment. The rear bodywork including engine cover, diffuser, winglets, radiator outlets, and exhaust chimneys were implanted from the MP4-18 while gearbox and rear suspension remained from the MP4-17D. Mercedes had developed a new injection system, a new exhaust and in addition to revised cylinder heads they gained 16 hp and were able to reduce fuel consumption. On the straight they were as fast as the BMW Williams, but with much less wing as you could easily see.
The pods have now been made lower towards the rear wing, and are smaller to attract more air towards both the rear wing and the diffuser. Another important change are the new exhausts. McLaren was since Magny-Cours the last of the top5 that was running an exhaust like Ferrari did in 2001. The pipes exited upwards at the top of the sidepod. Now, the exhausts are covered with like at Ferrari, leaving room for escaping hot air. The exhaust is now pointed towards the back, instead of upwards, which should be an advantage.
The McLaren MP4-18 has now definitely been buried and the car will never appear in a race. Pedro de la Rosa and Darren Turner completed 973 kilometres in a 3 day test in Jerez prior to Monza and neither driver was able to complete a race distance. Adrian Newey admits: "This car is the base for next years MP4-19."
Low downforce changes
At the Williams front there were some changes that weren't however very new. The new, slimmer front wing was equipped with a wide gurney flap at the end of the upper element. This will have increased downforce on the front wing, just like the small teeth on top of the rear wing did. These teeth were already seen at McLaren and on Ferrari front wings, and increase vortices. Of course this only occurs with a drag penalty, but apparently that didn't matter against the downforce gained.
Again, the chimneys were there at the Williams, which is already a familiar appearance. Since there was a smaller need of letting go the cooling air out of the sidebox, the covers around the engine exhausts that normally put out hot air around the exhausts, were removed, which left only the exhaust pipe visible about the end of the sidepods.
While Sauber is having a very difficult year, they seem to not have given up hope that they can catch more points with their car. A complete new cover for the sidepods was seen in training, and was very much inspired by the Ferrari way of building a sidepod. They have cut the size of the sidepod on top and at the end. This size decrease caused the air to be less efficient put out, which is why they also adopted the small air outlets from the sharky F2003-GA. However it is a good attempt, the real problem with this Sauber is the size of the inner elements. The season's beginning saw serious reliability problems due to overheating. It's not very clear how they have solved that, but you can clearly see the heat exchangers are wide and high, which hinders radical development of the aerodynamic side of the car. You can't build a sleek design around a car that is 20% larger than others.
Comparing the best
As the season comes to a close, I think a little comparison between the three topteams is in its place. It looks like this year is simply all about special shaped rear wings and sidepods. Therefore, the following picture may clear up some things. Let me first note the high amount of downforce run by Juan Pablo Montoya, which may eventually have cost him the victory. This high downforce level caused his rear tyres to blister quite rapidly, compared to lower downforce runners Raikkonen and Schumacher.
All three teams have their own philosophy about designing a side pod, with especially Williams having its own one. The side pod of the McLaren is ported back from the MP4/18, and is a little rounded at the outside. Just like the Ferrari, the pod is quite high at the beginning, but runs quickly down towards the end. Both of these cars have a flipup that starts around half the height of the sidepod, directing the air under the flipup to go towards the diffuser. Williams on the other hand puts the stress on low sidepods all over the length of them, which results in an flat roof (at the first half), but one that is visibly lower than the height of other car's side pods. Since less air is therefore changed of direction to flow over the sidepod, drag is reduced, and rear wing efficiency is increased. The flipup here is a lot wider and starts lower to the ground than that of the competitors. Also note the sidewall of the side pod, which is practically perpendicular to the track surface.
Finally there are front wings, where especially McLaren had set the trend by testing a new front wing for their new MP4/18. The second wing shows such a wing, as it was driven by Toyota at Monzo. Most of the teams however drive a Ferrari-bend, which is simple bent wing. Ferrari is running this spec for years now, and only Williams runs a different type (similar to the wing of Toyota in the image) when looking at the best 4 teams. As a one-timer, McLaren brought back the old style of front wings, which are nearly flat. This, in McLaren's case allows more air to flow under the car towards the diffuser. Apparently McLaren could better use some more traction than front grip in Monza
Aside from various new elements like a modified underbody, a new diffuser and new internal parts, Ferrari have (re)introduced some small things to increase performance. First of all there are the heat sensors that can measure the tyre temperature at all times. The presence of these sensors can be seen by the little bulge on the flipup before the rear tyre.
Another novelty was to be found in the pilane. Ferrari have covered the fuel hose with isolation material. As fuel can be best used in low temperatures (more molecules are together in the same volume), it is useful to not let the fuel warm up during refuelling. Therefore, to prevent the hose and the fuel within to warm up (even if it is only 0.5° C) engineers have covered it, so that it looks like a silver pipe.
Minardi also had a new aerodynamic part at Monzo. It was long since we had seen such a new part, but yet they have sort of copied the Ferrari flip-up and accompanying winglet. The triple layered old flip-up however was only replaced by the new one in free testing, and now during qualifying or race.