& now the Toorak Tracktors poke their heads back up
AUDI has vowed to stop increasing the size of its cars in a bid to keep weight under
control.
As the car industry wrestles with the problem of providing customers with the
comfort and safety they require while also meeting strict new fuel economy and emission
controls, Audi has made the decision to stop increasing the size of its cars.
For decades, Audi, as well as most mainstream car-makers, has constantly
increased the size of its vehicles with each new model introduction.
Total vehicle development leader, based at Audi’s Lightweight
Design Centre at Neckarsulm, has told our reporters that this practice had contributed to
a weight increase spiral and had to stop.
“We will not continue doing this,” he said.
“Our cars will not continue to increase.”
The VDL said the next Q7 SUV was an indication of its future policy.
“The new Q7 will not be larger,” he said.
“In fact, it will actually be a little bit smaller.”
While he said the process of making cars larger had worked in the past, it was now
out of line with customer demand.
“We are finding that due to cost effectiveness, many people are buying smaller cars,” he said.
“If we continue to make our cars larger and larger, people will not buy them.”
Audi points out that the weight saved by limiting vehicle size and using a range
of lightweight components will have a big effect on fuel consumption, as well as
making the cars more enjoyable to drive.
It claims that cutting a vehicle’s weight by 100kg has reduced fuel consumption by
between 0.3L/100km and 0.5L/100km.
Audi has long been at the forefront of lightweight design and has now produced
550,000 cars with aluminium bodies, but has been ramping up its efforts to cut weight from
vehicles as fuel consumption and reduced emissions become increasingly important.
Producing aluminium generates much more emissions than steel, owing to the
large amounts of electricity required, a fact that Audi does not doubt. It argues that the
emissions linked to aluminium are limited if the electricity is generated from renewable
sources.
Audi also claims that using significant amounts of aluminium is still a better
option for the environment, even when the electricity is generated by traditional
methods, because of the savings that come when the vehicle is in use.
“Because of the weight savings, the vehicle is using less fuel,”
The VDL also said.
“We estimate that the break-even point in terms of energy use for the aluminium
comes at around the halfway point of its life – anywhere from 20,000 to 50,000km.”
Apart from keeping the size of its vehicles in check, Audi is looking at using new
materials to shed weight. It already uses 11 different grades of steel on some models,
for optimum strength and minimum weight, but is now looking at increasing the amount
of aluminium, magnesium, plastics and carbon-fi bre-reinforced plastics.
Magnesium, one third lighter than aluminium, has long been used for select
components in premium cars and more widely on motorcycles, but Audi, along with
other car-makers, are using more of it and has even used die-cast magnesium for the
engine frame of its R8 supercar.
Audi says it will soon introduce more magnesium engine components for its
V6 engines, while a large transmission crossmember for the new A8 also will be
made from magnesium.
Audi this week displayed prototype components made of carbon-fi bre-reinforced
plastics that might soon replace aluminium components in its cars. One example was a
transverse suspension link which weighs 860g when made from steel sheet, but tips the scales
at 440g when made from the fi bre composite.
Audi is looking at all parts of the car and assembly processes in the bid to shave
kilos. For example, most car-makers stick heated bitumen mats to the fl oor of the car
for sound insulation. Audi has moved away from this process and now sprays the floor
with an acrylic substance used to seal joints in house construction.
It says this material is 25 per cent lighter, saving 12kg per vehicle, and is also better at
suppressing noise.
Audi also believes that the arrival of new hybrid and electric vehicles will make
weight reduction even more important.
“Batteries are very heavy,” the VDL said. “At this stage the weight of batteries is
an Achilles heel.”
