Interview with Willy Rampf, Technical Director of the BMW Sauber F1 Team.
"If we used our Monaco car in Monza we'd be over 50 km/h slower."
Munich/Hinwil, 4th September 2007. The Italian Grand Prix in Monza represents a
unique challenge for drivers and engineers alike. Willy Rampf, Technical
Director of the BMW Sauber F1 Team, explains how he and his colleagues go about
preparing for this race.
What makes Monza such a special track?
Willy Rampf, Technical Director: "Monza is a classic high-speed circuit with
extremely long straights, comparable only really with the old GP track at
Hockenheim. At four points during a lap, the drivers hit speeds well in excess
of 300 km/h and 76 percent of the lap is spent at full throttle. This is
significantly more than at any other Formula One track, and that is why we run
lower downforce at Monza than anywhere else over the course of the season."
What does that mean for the car's aerodynamics?
Rampf: "We have developed a 'low-downforce package' of special aerodynamic
parts for this race. At Monza we run less rear wing than at any other circuit.
And in order to achieve the right aero balance we have also redeveloped and
adapted the front wing. In addition, we examine the aerodynamic efficiency of
all the car's detachable parts for Monza. Only the most efficient of these are
left on the car. Indeed, we remove several elements, as doing so enhances
performance. We are taking the opposite approach to the way we prepare for
Monaco, for example, where we generally add every part to the car that will
generate extra downforce."
Staying with Monaco for a moment - how much less downforce do you run in Monza
compared to the street circuit in the principality?
Rampf: "In Monaco the cars only reach 290 km/h at one point on the circuit,
whereas in Monza they comfortably exceed 300 km/h in four places. For this
reason the engineers set out to minimise drag, and that means giving away
around a third of the car's downforce. In Monaco downforce is everything, while
in Monza the drag coefficient plays a major role. Having said that, you can't
afford to neglect downforce altogether. After all, the drivers also need to be
able to brake late and accelerate quickly through the corners."
How do the top speeds of the two tracks compare with one another?
Rampf: "The low-downforce package allows the F1.07 to hit a maximum speed of
around 350 km/h at the end of the start/finish straight in Monza. If we were to
run the car in Monaco specification the drivers would not reach 300 km/h, as
the engine output would no longer be sufficient to overcome the mushrooming air
resistance."
How did the contributions of the wind tunnel and the supercomputer with Intel
processors compare in the development of the aero parts?
Rampf: "The two are closely intertwined. The development of these parts
involves interaction between the knowledge gained in the wind tunnel and the
results of computer-aided flow simulation, otherwise known as Computational
Fluid Dynamics (CFD). CFD and the wind tunnel are mutually beneficial. CFD has
advantages when it comes to the development of wing concepts, for example. The
wind tunnel, on the other hand, is unsurpassed in perfecting the car's overall
aerodynamic set-up."
How do you adapt the car mechanically for the Monza circuit?
Rampf: "In addition to achieving the highest possible top speed, it is also
critical for the drivers to be able to drive aggressively over the kerbstones.
The track features three chicanes leading into full-throttle sections. It is
important to nail a fast exit from these corners, and to do that you need
sufficient traction. The mechanical set-up of the car represents a tricky
compromise. It has to be soft enough to ride the kerbs efficiently and provide
good traction, but go too soft and you'll be short on stability through the
high-speed corners."
What kind of stress do these track characteristics place on the brakes?
Rampf: "When it comes to the brakes, Monza literally blows hot and cold. On the
one hand the long straights give them a lot of time to recover, but braking
from seriously high speeds generates extreme loads every time. The end of the
start/finish straight is the hardest braking zone of the entire season, the
drivers slowing from 350 km/h to 70 km/h within the space of three seconds and
enduring maximum deceleration of 5 g. The brake discs, meanwhile, briefly reach
temperatures of well over 1,000 degrees Celsius. What makes braking under these
conditions particularly tricky is that on the long straights the carbon discs
cool down more than the drivers would like - to under 400 degrees. When they
then stamp down with some 100 kilograms of pressure on the brake pedal, for a
split second or two the brakes do not bite with full power. That is something
the drivers have to be prepared for."
And what about the loads on the engine?
Rampf: "Monza makes the engines work harder than at any other GP. This circuit
boasts the highest full-throttle percentage - 76 percent - of any venue on the
calendar. This means that the engines are running for exceptionally long
periods at high revs. However, we don't expect any problems since the
homologated engines are designed to withstand loads of this order."
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