This mod is Mack E7 engine with straight pipe sound for Mack R Series by Harven, Mack Superliner by Dielingwu and Mack Pinnacle CHU613 by Frank Peru

Latest Version Feature:

-Mack E7 250-460hp engines with straight pipe sound

-Realistic turbo behavior

-3 stages jake brake

-Improved custom sound attenutaion for realistic sound fade off and distortion

-Improved custom exhaust distortion for realistic exhaust sound and work along with attenuation

-Idle jake brake system

How to use idle jake brake:

1. hold light horn button (J button) for 1 second, then release

2. tap light horn button once again, and idle jake brake should be engaged

3. Repeat the same process to turn off 

Note: idle jake brake is not compatible with the mods that have interior switches sound

(sound fixes pack is exceptional but put my mod on top piority)

Credits:

Slav Jerry - sound samples, mixing and modding