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Demonstrate knowledge of exhaust system tuning for performance and
noise in competition race vehicles
Level
5
Credits
4
Purpose
This theory-based unit standard is for people who work in a motorsport
environment. People credited with this unit standard are able to demonstrate
knowledge of performance exhaust system considerations and features, and
determine exhaust system tuning requirements for performance and noise to
suit particular competition race vehicles.
Subfield
Motor Industry
Domain
Automotive Fuel Systems and Exhaust
Status
Registered
Status date
25 June 2007
Date version published
25 June 2007
Planned review date
31 December 2012
Entry information
Open.
Accreditation
Evaluation of documentation and visit by NZQA and
industry.
Standard setting body (SSB)
NZ Motor Industry Training Organisation
Accreditation and Moderation Action Plan (AMAP) reference
0014
This AMAP can be accessed at http://www.nzqa.govt.nz/framework/search/index.do.
Special notes
1
Publications relevant to this unit standard include but are not limited to – MotorSport
New Zealand regulations, New Zealand MotorSport Manual No 33.
2
The MotorSport New Zealand regulations (motorsport regulations) and the New
Zealand MotorSport Manual (motorsport manual) are available from the MotorSport
New Zealand website http://www.motorsport.org.nz/. The Motorsport Manual is
subject to frequent amendment, and any amendments will take precedence for
assessment purposes, pending the review of this unit standard.
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3
Definitions
Company requirements refer to instructions to staff on policy and procedures which
are documented in memo or manual format and are available in the workplace.
These requirements include but are not limited to – company specifications and
procedures, work instructions, manufacturer specifications, product quality
specifications, and legislative requirements.
Service information may include but is not limited to – technical information of a
vehicle, machine, or product detailing operation; installation and servicing
procedures; manufacturer instructions and specifications; technical terms and
descriptions; and detailed illustrations. This can be accessed in hard copy or
electronic format and is normally sourced from the manufacturer.
Header is another name for a manifold, and specifically refers to an enhanced
manifold that has been designed for performance.
Crossovers refer to a tangentially Siamese crossover junction to synchronize exhaust
pulses on a vee-type engine.
Header-back refers to the portion of the exhaust system from the outlet of the header
to the final vent to open air – everything from the header back. Header-back systems
are generally produced as aftermarket performance systems for vehicles without
turbochargers.
Turbo-back refers to the portion of the exhaust system from the outlet of a
turbocharger to the final vent to open air.
Cat-back refers to the portion of the exhaust system from the outlet of the catalytic
converter to the final vent to open air. This generally includes the pipe from the
converter to the muffler, the muffler itself, and the final length of pipe to open air.
Elements and performance criteria
Element 1
Demonstrate knowledge of performance exhaust system considerations and features.
Performance criteria
1.1
Motorsport requirements relating to the exhaust system of a competition race
vehicle are explained in accordance with motorsport regulations.
Range
1.2
Performance exhaust system considerations are identified in accordance with
company requirements.
Range
1.3
noise level, mounting, gas leakage, isolation, outlet position and
protrusion.
includes but is not limited to – performance, appearance, sound,
durability, economy.
Performance system features are described in accordance with service
information.
Range
includes but is not limited to – material, exhaust gas flow,
diameter, appearance, sound absorption.
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1.4
Types of exhaust system kits are described in accordance with service
information.
Range
1.5
includes but is not limited to – down-swept and up-swept manifold
(header or extractor), pipes, crossovers and balance pipes,
mufflers (sound rated), accessories (collection reducers, splitters,
downturns, tips);
header-back kit, turbo-back kit, cat-back kit.
The purposes of mandrel bending, slip-fit joints, and flange joints are identified
in accordance with service information.
Element 2
Determine exhaust system tuning requirements for performance and noise to suit
particular competition race vehicles.
Performance criteria
2.1
The importance of gas velocity and uninterrupted flow as factors in the tuning of
exhausts are explained in accordance with service information.
2.2
The requirements of muffler and balance and cross-pipe design to tune sound
waves and reduce resonance to meet event requirements are explained in
accordance with service information.
2.3
How exhaust system tuning affects combustion chamber scavenging, exhaust
pressure, and the incoming fuel-air mixture is explained in accordance with
service information.
2.4
The use of a dynamometer to test engine torque and exhaust noise changes
using combinations of components in the exhaust system is explained in
accordance with company requirements.
2.5
The importance of matching exhaust system specifications to engine
requirements is explained in accordance with company requirements.
2.6
The use of a flow bench to test muffler flow rates is explained in accordance
with company requirements.
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Please note
Providers must be accredited by NZQA, or an inter-institutional body with delegated
authority for quality assurance, before they can report credits from assessment against
unit standards or deliver courses of study leading to that assessment.
Industry Training Organisations must be accredited by NZQA before they can register
credits from assessment against unit standards.
Accredited providers and Industry Training Organisations assessing against unit standards
must engage with the moderation system that applies to those standards.
Accreditation requirements and an outline of the moderation system that applies to this
standard are outlined in the Accreditation and Moderation Action Plan (AMAP). The
AMAP also includes useful information about special requirements for organisations
wishing to develop education and training programmes, such as minimum qualifications for
tutors and assessors, and special resource requirements.
Comments on this unit standard
Please contact the NZ Motor Industry Training Organisation jlane@mito.org.nz if you wish
to suggest changes to the content of this unit standard.
 New Zealand Qualifications Authority 2016