Kia 2004.5 Spectra Service Technical Training page 146

2004.5 Spectra Technology
SULEV CATALYTIC CONVERTER
This type of CAT has complex internal structures with
800 to 1000 cpsi substrates and wall thickness down
to 0.025 mm. This progress in ceramic and metal
substrate technology has major benefits. A larger
catalyst surface area can be incorporated into a given
converter volume, which allows better conversion
efficiency and durability. The thin walls reduce thermal
capacity and avoid the penalty of increased pressure
losses.
Alternatively, the same performance can be
incorporated into a smaller converter volume, making
the catalyst easier to fit close to the engine, as in the
Spectra. The use of additional catalytic converters
close to the exhaust manifold reduces the time to
warm up at cold start and, therefore, the total
emissions. Warm up time has been reduced from as
long as one to two minutes to less than 20 seconds.
Improved substrate technology, combined with highly
thermally stable catalysts and oxygen storage
components, allows the close-coupled catalyst
approach to meet the California Low Emission Vehicle
(LEV), Ultra Low Emission Vehicle (ULEV) and Super
Ultra Low Emission Vehicle (SULEV) regulations.
Driveability
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