HOW FAST IS A LE MANS CAR?
"The Le Mans Nissan R390 GT1 makes a fast road car, even something like
a Nissan Skyline GT- R, look like a vintage car, the speed is so
phenomenal," explains Nissan Le Mans star John Nielsen. "The grip, the
acceleration, and the braking is absolutely incredible. They are not
far off a Grand Prix car and F1 cars are built to race only for 90
minutes not 24 hours!"
After reliability, top speed is the most important factor in building a
potential race winner for the most exacting endurance race of them all -
the Le Mans 24-Hours.
"Five times, on each lap of Le Mans, the car is doing over 300 kph.
To get an extra kilometre or two an hour out of the car each time it
reaches top speed makes a huge difference after 24 hours," explains
engineer Steve Farrell, the technical brains behind Nissan's lightning
quick R390 GT1. Farrell does not under-estimate the importance of
winning the 300 kph plus race down the Mulsanne Straight, but has other
considerations too.
"We could make the car even faster on the straights, but we also have to
make the car comfortable to drive through the corners," says Le Mans
veteran Farrell, who knows that the drivers have to complete over 350
laps of the 13 mile La Sarthe circuit. "We could even take the rear
wing off, but as well as an extra 20 kph it would make the car
potentially dangerous too."
To watch these thundering sports cars, each pumping out up to 500 bhp -
eight times the average family car - as they power down the Mulsanne
Straight, is one of the great sights in motor sport. Howling through
the trees on a road that for the rest of the year is a public highway,
the cars break the 300 kph barrier with ease. Some even break 350 kph,
three times most countries' speed limit!
"To be honest, when you're driving it's hard to tell the difference
between 300 and 350 kph," says former Le Mans winner and key Nissan
driver Jan Lammers. "In the old days when there were no chicanes on the
Mulsanne and it was five miles long, the cars could get closer to
375 kph. But now 350 is a competitive maximum."
"A faster race is better for the driver, because it keeps you alert.
Although this is not Formula 1, where you squeeze every last thousandth
of a second out of each lap, if you don't set yourself a fast rhythm,
then it is easy to drift off the pace," says the Dutchman. "That is
not likely to happen with the Nissan. It is an incredibly fast car and
on each lap I will be pacing myself by trying to hit the same apexes,
the same braking points and by counting down the remaining laps."
The Nissan R390 GT1's speed has never been in question. Since the day
it first ran in 1997, then setting the fastest time in pre-qualifying,
the sleek design has been a pacesetter.
"Anyone can make a car fast," says Nissan's Le Mans project director
Kunihiko Kakimoto. "But it is always pleasing to make the fastest car.
This year we aim to be the fastest at the beginning, but at the end as
well."
The key to speed is aerodynamics, says the car's designer, Tony
Southgate. Southgate has designed victorious Le Mans and Formula 1
cars. "I handed the team the fastest possible design I could manage, a
car we knew from scale model tests would be fast. We could predict its
top speed with incredible accuracy, but still to see it run fast is very
exhilarating."
Last year the precise aerodynamic characteristics of the R390 had to be
modified at the last moment. As a result the car's running temperature
was hotter than planned, which in turn affected reliability.
"This year we have modified the aerodynamics, but that has not
compromised the overall design of the car," says Southgate. "This year's
Le Mans car is in fact a little faster and at the same time we have been
able to increase downforce without losing speed."
The downforce is the pressure exerted on the car as it runs through the
air. The faster the speed, the more downforce is generated. At 300 kph
the downforce is massive.
"We calculate that on the Mulsanne straight the car doubles in weight
because of the downforce, much of it generated by the massive rear
wing," says Southgate. "That's good. It makes the car stick to the
road better, which at those speeds is crucial."
This means that, the fastest parts of the Le Mans track are the most
relaxing for the drivers. On the old Mulsanne Straight, there was time
for the drivers to do some stretching exercises and prepare themselves
for the next lap.
"That has changed," says John Nielsen. "Now the straight is shorter
and if there is another car on the straight at the same time, you have
to be very sure he has seen you. There is still a short time to
stretch but this is still the part of the track where we try to do most
of our overtaking.
"The risks of overtaking on the straight are fewer than in the corners
and it is less stressful on the car. The key to success at Le Mans is
to try and drive gently but very fast. I am not going to get into a
battle through the corners. I will wait and take the guy on the
straight."
The fastest time of the race, which also comes as the drivers dip into a
mental and physical trough, is just before dawn. High humidity, low
temperatures and plenty of rubber on the track makes the pre-dawn hours
the time when new records are regularly broken.
Predictably, braking is as important as speed. The Nissan R390 GT1 has
ABS, or anti-lock brakes, assisting its massive brakes.
"If I was to take you out in the Nissan, the brakes would amaze you
even more than the top speed or the acceleration. Don't forget this car
is twice as heavy as a Grand Prix car with about the same power. But
the thing which would stick in your mind would be the incredible
braking," says John Nielsen.
"The braking points we have are so late that physically it puts a lot of
pressure on your body. You feel as if you are about to go out of the
windscreen the G-forces are so immense. It means we can brake much
later than our rivals."
The immense braking pressures, up to 3G, gives the driver a significant
advantage, but puts a lot of extra pressure on the car. Kakimoto is
confident that the car is strong enough to endure such punishment over
24 hours.
"The adoption of ABS will save us time," he says. "In addition our
extra top speed this year will give us three seconds and the improved
tyres a little more. If our rivals have done better then I shall walk
up and shake their hands, but we are confident we have a car fast enough
to win."