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Vehicle and Engine Certification

Heavy-Duty Highway Gasoline (Otto-cycle/Spark Ignition) Engines (>8500 Pounds GVWR): Family Naming Conventions

To determine Positions 1-4 of your Engine Family name, see:

Use the table below to create Positions 5-12:

Location in Family Name Code/Value Description or Instructions
Position 5 E Industry sector code for all "Heavy-Duty Highway Gasoline (otto-cycle/spark ignition) Engines (>8500 pounds GVWR) "
Positions 6-9 XX.X or
.XXX
Engine displacement units in liters
(decimal point counts as a digit and each 'X' represents an integer)
XXXX Engine displacement units in cubic inches
(each 'X' represents an integer)
SPEC Spark-ignition Specialty Vehicle Engines
Positions 10-12 *** Enter any combination of valid characters in order to provide a unique identification for your family name.