Under the current 04 series of amendments to UN Regulation No. 41, the engine speed should be measured during all tests in Annex 3 and Annex 7 (Additional sound emission provisions – ASEP). However, IMMA has found that there is very little difference between the measured and the calculated engine speed for a manual transmission (MT) vehicle (Annex, figure 1) and no impact on the test result (Annex, figure 2). Therefore, this proposal would introduce a calculated engine speed for MT vehicles and for continuously variable transmission (CVT)/automatic transmission (AT) with locked gear mechanism into UN Regulation No. 41.
6. The expert from IMMA proposed to introduce the calculated engine speed for various types of transmission into Regulation No. 41 (ECE/TRANS/WP.29/GRB/2015/2 and Corr. 1, Corr. 2). GRB adopted the proposal and mandated the secretariat to submit it to WP.29 and AC.1 for consideration and vote at their June 2015 sessions as a draft Supplement to Regulation No. 41.