Whereas for last year's car numerous components had already been designed when BMW resolved to buy the majority shareholding in Sauber in June 2005, the F1.07 was a co- production from its inception. Those responsible for the chassis in Hinwil and their colleagues in Munich handling the powertrain (i.e. the engine and transmission) and the electronics, jointly laid down priorities and created a harmonious overall package.

Work on the concept for the F1.07 began in April 2006. "On the one hand we channelled our experience from the F1.06 into the car, but at the same time we considered the new challenges presented by the 2007 regulations," explains Willy Rampf, Technical Director of the BMW Sauber F1 Team.

Set-up based on standard tyres lends aerodynamics even greater importance. The most important change here is undoubtedly the switch to standard tyres supplied by Bridgestone which, in keeping with the FIA stipulations, must provide less grip so as to reduce cornering speeds. "It is obvious that the cars are going to slide around more, and so it was important for us to build a car that is easy to drive and that our drivers can trust sufficiently to go on the attack," explains Rampf. "We should also expect the cars generally to run with slightly more downforce in order to compensate for the loss of grip."

With the introduction of standard tyres, the significance of aerodynamics increases even more. "If you look at all the components that affect the performance of a Formula One car, aerodynamics represent by far the single most important factor," Rampf is at pains to point out. That is why the expansion of the aerodynamics division was given top priority. Operation of the wind tunnel in Hinwil was gradually ramped up from one to two and then, at the end of October 2006, three shifts. That has long been standard among the competition and was a key prerequisite for achieving the team's ambitious targets.

Beyond efficient aerodynamics, this time round it is almost equally important to develop a car that responds as well as possible in corners. The front wing has a major role to play here as it definitively dictates the flow of air around the front tyres. Hence it is an all-new development which forms a harmonious coupling with the likewise totally new vehicle nose, which is now shorter and sits higher. This naturally brings a reduction in its weight, but it places extra demands on the engineers in terms of passing the FIA crash tests. However, the most important aspect is that the wing channels a large amount of air under the car, allowing the underbody and diffusor to work to full potential.

The cooling intakes are somewhat larger than those in the predecessor model. They are part of the new cooling concept, which is more effectively integrated into the car's overall package and designed for a greater throughput of air. The air is smoothly diverted upwards, improving aerodynamic efficiency by comparison with the F1.06 particularly in high outside air temperatures. As Rampf points out: "In the concept phase we devoted a lot of time to finding an optimal solution in this area. It's an important factor as the air temperature in the first races of the season in particular are traditionally very high. The cooling concept of the F1.07 promises to deliver very high efficiency in all conditions."

In developing the rear of the car, the designers built on the knowledge gained with the F1.06, giving the tail an even slimmer and lower profile to further optimise air flow around the rear wing. This design was based on the compact quick shift gearbox as well as cleverly positioned hydraulic elements. Also harmoniously integrated into the design are the exhaust pipes, whose form was determined by considerations of performance and overall package.