This mod is Cat 3406B engine and straight pipe sound for SCS Peterbilt 389, Kenworth W900
and some modded trucks

Feature:
-Cat 3406B 310hp, 350hp, 425hp engine with straight pipe sound
-Custom exhaust distortion sound for more realistic acceleration
-Custom sound attenuation for realistic sound fade off
-Custom sound orientation for realistic sound from different angle

Credits
Slav Jerry - sound modding and samples
SCS Software - sound samples