mandated by the sanctioning
body for noise requirements,
such as in endurance races
to help alleviate noise fatigue.
When you are racing for 24
hours the fatigue caused by the
noise of the engine can cause
a driver to become fatigued or
lose concentration over time."
The type of metal used on
racing exhaust systems is also
important to handle extreme
temperatures and durability.
"Our header builders will use
various grades of stainless steel
for the header systems," said
Kroyer. "Different grades may
be dictated by how hot the
actual exhaust gas temperature
is in combination with the
longevity/ life span of the
headers. We prefer a multilayer
ceramic based coating on our
headers and exhaust systems."
Because mufflers are often
used on desert racing vehicles,
the concern over back pressure
is another vital aspect of a
racing exhaust system. "Exhaust
back pressure is a function
of trying to get the exhaust
charge out of the cylinder and
out to the atmosphere, too
much resistance caused by
too small an exit pipe, or to
restrictive a muffler can actually
inhibit the engines ability to
get the exhaust charge out of
the engine and then result in
not as efficient cylinder filling
during the intake phase of the
4-stroke combustion process."
Ray Field, 2015 SCORE Engine
Builder Of The Year award
winner, is owner of Dougans
Racing Engines in Riverside,
California. His observations
on racing exhaust systems are
similar to Kroyer's and include
various amounts of testing to
find the best combinations. "We
RACING EXHAUST SYSTEMS AREN'T JUST FOR BIG HORSEPOWER ENGINES.
ADRIAN ORELLANA IS ONE OF MANY PROFESSIONAL UTV DESERT RACERS
WHO USE A PERFORMANCE EXHAUST, THIS ONE BEING A GIBSON.
068
SCORE JOURNAL
COURTESY
GIBSON
PERFORMANCE
