Division 2.4 Parameters defining the tailpipe emissions in-service familyF1

The in-service family may be defined by basic design parameters which shall be common to vehicles within the family. Accordingly, vehicle types may be considered as belonging to the same in-service family if they have in common, or within the stated tolerances, the following parameters:

1. 2.4.1.

   combustion process (two stroke, four stroke, rotary);

2. 2.4.2.

   number of cylinders;

3. 2.4.3.

   configuration of the cylinder block (in-line, V, radial, horizontally opposed, other. The inclination or orientation of the cylinders is not a criteria);

4. 2.4.4.

   method of engine fuelling (e.g. indirect or direct injection);

5. 2.4.5.

   type of cooling system (air, water, oil);

6. 2.4.6.

   method of aspiration (naturally aspirated, pressure charged);

7. 2.4.7.

   fuel for which the engine is designed (petrol, diesel, NG, LPG, etc.). Bi fuelled vehicles may be grouped with dedicated fuel vehicles providing one of the fuels is common;

8. 2.4.8.

   type of catalytic converter (three-way catalyst, lean NO _x trap, SCR, lean NO _x catalyst or other(s));

9. 2.4.9.

   type of particulate trap (with or without);

10. 2.4.10.

    exhaust gas recirculation (with or without, cooled or non-cooled); and

11. 2.4.11.

    engine cylinder capacity of the largest engine within the family minus 30 %.