Document ID: chunk:federal_register_of_legislation:F2023L00129:reg:20:p18
Version: federal_register_of_legislation:F2023L00129
Segment Type: reg
Provision Reference: reg 20 (pt 18/29)
Character Range: 268539–271398

are respected. The engine family shall be approved by the Type Approval Authority. The manufacturer shall provide to the Type Approval Authority the appropriate information relating to the emission levels of the members of the engine family.
5.2.2. Special cases
 In some cases there may be interaction between parameters. This shall be taken into consideration to ensure that only engines with similar exhaust emission characteristics are included within the same engine family. These cases shall be identified by the manufacturer and notified to the Type Approval Authority. It shall then be taken into account as a criterion for creating a new engine family.
 In case of devices or features, which are not listed in paragraph 5.2.3. and which have a strong influence on the level of emissions, this equipment shall be identified by the manufacturer on the basis of good engineering practice, and shall be notified to the Type Approval Authority. It shall then be taken into account as a criterion for creating a new engine family.
 In addition to the parameters listed in paragraph 5.2.3., the manufacturer may introduce additional criteria allowing the definition of families of more restricted size. These parameters are not necessarily parameters that have an influence on the level of emissions.
5.2.3. Parameters defining the engine family
5.2.3.1. Combustion cycle
(a) 2-stroke cycle;
(b) 4-stroke cycle;
(c) Rotary engine;
(d) Others.
5.2.3.2. Configuration of the cylinders
5.2.3.2.1. Position of the cylinders in the block
(a) V;
(b) In line;
(c) Radial;
(d) Others (F, W, etc.).
5.2.3.2.2. Relative position of the cylinders
 Engines with the same block may belong to the same family as long as their bore center-to-center dimensions are the same.
5.2.3.3. Main cooling medium
(a) Air;
(b) Water;
(c) Oil.
5.2.3.4. Individual cylinder displacement
5.2.3.4.1. Engine with a unit cylinder displacement ≥  0.75 dm³
 In order for engines with a unit cylinder displacement of ≥  0.75 dm³ to be considered to belong to the same engine family, the spread of their individual cylinder displacements shall not exceed 15 per cent of the largest individual cylinder displacement within the family.
5.2.3.4.2. Engine with a unit cylinder displacement < 0.75 dm³
 In order for engines with a unit cylinder displacement of < 0.75 dm³ to be considered to belong to the same engine family, the spread of their individual cylinder displacements shall not exceed 30 per cent of the largest individual cylinder displacement within the family.
5.2.3.4.3. Engine with other unit cylinder displacement limits
 Engines with an individual cylinder displacement that exceeds the limits defined in paragraphs 5.2.3.4.1. and 5.2.3.4.2. may be considered to belong to the same family with the approval of the Type Approval Authority. The approval shall be based on technical