Demon sound as best as I can get it to
INSTRUCTIONS
Extract all files from zip folder
Go to mods/update/x64/dlcpacks
drag and drop the demonengine folder
NEXT GO TO mods/update/update.rpf/commom/data
USE THIS DLC LINE

dlcpacks:\demonengine\

I RECOMMEND USE THE HANDELING.META FOR THE TRUE DOGE DEMON FEEL
use tk0wnz challenger here
https://www.gta5-hub.com/vehicles/2015-dodge-challenger-add-on-stock-shaker-hellcat