Since we're in Spa 24 Hours race week, I'm giving you this nice V8 sound to add variety to your GT3 class.
Here's what you need to do in order to have the best experience possible:
1: The straigh-cut gears is synced to the following gear ratio:
GEAR_1=2.5000
GEAR_2=1.8947
GEAR_3=1.5600
GEAR_4=1.3076
GEAR_5=1.1333
GEAR_6=1.0000
FINAL=3.1333
GEAR_2=1.8947
GEAR_3=1.5600
GEAR_4=1.3076
GEAR_5=1.1333
GEAR_6=1.0000
FINAL=3.1333
2: Max RPM is 7000, min is 2100; Turbo max boost 0.96; WASTEGATE=0.525
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The recommend audio settings inside AC:
Engine: 10
Everything else: 5
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This sound should work with any car as long as the transmission, engine and turbo values aren't too different. Use Content Manager to replace the sound and you're done. Just don't forget to backup the original sound before.
Credits goes to 19Bozzy92 for the external sounds.