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Therefore it’s
no surprise that the correct oil mixtures produced synthetically by the
Formula 1 suppliers has to be determined and constantly adapted as part of a
complicated procedure. It’s also no surprise that manufacturers such as
Castrol, Mobil and Shell keep their chemical formulas under lock and key –
just like the tyre manufacturers. One thing is certain, the oil used in
Formula 1 is extremely free-flowing and almost has the consistency of water;
this at first seems somewhat surprising, because high-viscosity oil would
cool better. However, low-viscosity oil allows the engine to rotate faster.
“The lubricant determines the so-called friction coefficient between the
engine parts that slide over each other,” says Dr David Hall, Head of
Lubrication Development at Castrol. “The lower it is, the easier and faster
all the parts can move. Therefore, low friction results in higher speeds,
along with lower friction loads on the components and a reduction in fuel
consumption.”
The oil supplier provides roughly 30,000 litres of engine oil, as well as
3,000 litres of gearbox oil, for Formula 1 cars (which includes races,
testing and benchwork). For each race event Castrol supplies approximately
200 litres of engine oil and 75 litres of gearbox oil.
As so often in motorsport, lubricants have to achieve a compromise between
performance and reliability. If the oil is too thin, then it may lead to
premature faults, such as damage to the engine or gearbox. Weight also plays
a role: thinner oil does not conduct heat so well. For this reason more of
it has to be used, which in turn increases the car’s weight.
The engine contains roughly 10 litres of oil, of which seven litres are
located in the crankcase and cylinder area. “During testing, the engine oil
is renewed on a daily basis”, says Dr Hall, “sometimes some oil is drained
off, when various oil levels are being tested as part of different set-ups.”
The optimum composition of the lubricants is determined by the manufacturers
with the help of a computer – this applies both to passenger car production
and motor-sport. For the latter, however, differentiations are also made
from race track to race track. For instance, at narrow tracks, such as at
Monaco, the teams opt for a high-viscosity oil. This is because the high
load, due to permanent changing between acceleration and braking at high
speeds in low gears, causes the temperatures in the engine to rise higher
than normal.
Finding the ideal mixture is a long process: the oils mixed in the computer
are produced in small quantities for testing purposes. If these prove to be
successful, then the lubricant has to be tested by Formula 1’s ruling body,
the International Automobile Federation (FIA), to see whether it complies
with regulations. Only then are larger quantities produced, which in turn
are subject to constant purity monitoring.
The most important task for the developers doesn’t start until the weekend
of the race. The specialists at the track take oil samples from the Formula
1 cars each time they come back in after a practice session. By using X-ray
equipment they can detect any metal residue which makes its way into the oil
due to engine and gearbox wear. This means that under certain conditions
engine damage can be avoided. Depending upon the oil’s degree of impurity,
the engineers can then decide whether a part may have to be replaced
straight away.
Indeed, nowadays it is even possible to control the oil flow by computer
during a race. This in turn means that any impending faults can be avoided
in advance, thus allowing spectators at Monza to enjoy the full sound of the
engine – lap after lap.
In passenger cars, engine oil must not only lubricate moving parts, it must
also perform a variety of other tasks. Frictional heat must be dissipated,
wear particulates must be removed and contamination flushed out. In
addition, corrosion protection must be provided for the engine. To ensure
that the engine oil can fulfil all these tasks the basic oil has up to 20
percent additives added to it, from viscosity index enhancers for better
temperature properties on to dispersants and anti-wear additives. Fully
synthetic basic oils, as used in Formula 1, are also making their way into
passenger car production.
“Fully synthetic low-viscosity oils can, in particular, lower fuel
consumption for short-distance traffic by up to five percent”, says Dr
Christoph Lauterwasser from the Allianz Centre for Technology (AZT) in
Munich. “Of course, they are significantly more expensive than conventional
oils; the reduction in fuel consumption, however, compensates for this
effect. In addition, where cold starting takes place frequently, the engine
is better preserved by the improved lubricating property and flow behaviour.
An additional positive effect also applies to diesel engines: particulate
emissions are significantly lowered.”
However, even the finest of oils have to be changed on a regular basis, even
if some manufacturers are increasing the service intervals. Here, it is
essential to adhere to the oil specifications prescribed by the
manufacturer. Anyone choosing to change the oil by themselves should – for
reasons of environmental protection – observe cleanliness and make sure that
the used oil is disposed of properly. All dealers that sell oil are obliged
to accept any used oil that is returned. |
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